diff --git a/Bugzilla/Comment.pm b/Bugzilla/Comment.pm
index 33cfddba4..66c842c28 100644
--- a/Bugzilla/Comment.pm
+++ b/Bugzilla/Comment.pm
@@ -30,6 +30,8 @@ use Bugzilla::User;
 use Bugzilla::Util;
 use Bugzilla::Template;
 
+use Data::Dumper;
+
 ###############################
 ####    Initialization     ####
 ###############################
@@ -92,7 +94,6 @@ sub preload {
 ###############################
 
 sub already_wrapped { return $_[0]->{'already_wrapped'}; }
-sub body        { return $_[0]->{'thetext'};   }
 sub bug_id      { return $_[0]->{'bug_id'};    }
 sub creation_ts { return $_[0]->{'bug_when'};  }
 sub is_private  { return $_[0]->{'isprivate'}; }
@@ -101,6 +102,21 @@ sub type        { return $_[0]->{'type'};      }
 sub extra_data  { return $_[0]->{'extra_data'} }
 sub who         { return $_[0]->{'who'};       }
 
+sub body
+{
+    my ($self, $preview) = @_;
+    $preview = 0 if !$preview;
+    if ($preview && !$self->check_length)
+    {
+        my $max_lines = Bugzilla->params->{preview_comment_lines} - 1;
+        my $line_length = Bugzilla->params->{comment_line_length} - 1;
+        my $result = $self->{'thetext'};
+        $result =~ s/^((?>[^\n]{0,$line_length}.){0,$max_lines}(?>[^\n]{0,$line_length}\s)).*$/\1.../s;
+        return $result;
+    }
+    return $_[0]->{'thetext'};
+}
+
 sub bug {
     my $self = shift;
     require Bugzilla::Bug;
@@ -134,6 +150,7 @@ sub author {
 sub body_full {
     my ($self, $params) = @_;
     $params ||= {};
+    my $preview = $params->{preview} ? $params->{preview} : 0;
     my $template = Bugzilla->template_inner;
     my $body;
     my $t = $self->type;
@@ -146,17 +163,36 @@ sub body_full {
         $body =~ s/^X//;
     }
     else {
-        $body = $self->body;
+        $body = $self->body($preview);
     }
     if (!$params->{is_bugmail}) {
         $body = Bugzilla::Template::quoteUrls($body, $self->bug_id, $self);
     }
     if ($params->{wrap}) {
         $body = wrap_comment($body);
+        if (!$preview && !($self->check_length))
+        {
+            $params->{preview} = 1;
+            my $new_body;
+            $template->process("bug/comment-preview-text.html.tmpl",
+                               { preview => $self->body_full($params), body => $body, id => $self->id }, \$new_body)
+                || ThrowTemplateError($template->error());
+            $body = $new_body;
+        }
     }
     return $body;
 }
 
+sub check_length
+{
+    my $self = shift;
+    my $test = $self->{'thetext'};
+    my $line_length = Bugzilla->params->{comment_line_length};
+    my $length = $test =~ s/([^\n]{$line_length}|\n)/$1/g;
+    $length = 0 if !$length;
+    return $length <= Bugzilla->params->{preview_comment_lines};
+}
+
 ############
 # Mutators #
 ############
diff --git a/Bugzilla/Config/BugFields.pm b/Bugzilla/Config/BugFields.pm
index b212f7880..6a06268be 100644
--- a/Bugzilla/Config/BugFields.pm
+++ b/Bugzilla/Config/BugFields.pm
@@ -197,6 +197,20 @@ sub get_param_list {
    type => 'b',
    default => 0,
   },
+
+  {
+   name => 'comment_line_length',
+   type => 't',
+   default => '80',
+   checker => \&check_numeric
+  },
+
+  {
+   name => 'preview_comment_lines',
+   type => 't',
+   default => '30',
+   checker => \&check_numeric
+  },
   );
   return @param_list;
 }
diff --git a/js/bug.js b/js/bug.js
index ca7590939..f5909bc86 100644
--- a/js/bug.js
+++ b/js/bug.js
@@ -49,6 +49,28 @@ function showhide_comment(comment_id, show)
         addClass(comment, 'collapsed');
 }
 
+function showhide_comment_preview(comment_id)
+{
+    var link = document.getElementById('comment-preview-link-' + comment_id);
+    var preview = document.getElementById('comment-preview-' + comment_id);
+    var body = document.getElementById('comment-body-' + comment_id);
+    var show = link.className.match(new RegExp(/\bshown\b/))
+    if (show)
+    {
+        preview.style.display = 'block';
+        body.style.display = 'none';
+        removeClass(link, "shown");
+    }
+    else
+    {
+        preview.style.display = 'none';
+        body.style.display = 'block';
+        addClass(link, "shown");
+    }
+    link.innerHTML = (!show ? "Hide" : "Show") + " full text";
+    return false;
+}
+
 // Mark comment as worktime-only or normal
 function toggle_wtonly(id, initial_wtonly, img)
 {
diff --git a/template/en/custom/bug/comment-preview-text.html.tmpl b/template/en/custom/bug/comment-preview-text.html.tmpl
new file mode 100755
index 000000000..03ef77e5c
--- /dev/null
+++ b/template/en/custom/bug/comment-preview-text.html.tmpl
@@ -0,0 +1,5 @@
+<div id="comment-preview-[% id %]">[% preview %]</div>
+<div id="comment-body-[% id %]" style="display:none;">[% body %]</div>
+<p style="text-align: right">
+    <a href="javascript:void(0)" id="comment-preview-link-[% id %]" onclick="return showhide_comment_preview([% id %])">Show full text</a>
+</p>
diff --git a/template/en/default/admin/params/bugfields.html.tmpl b/template/en/default/admin/params/bugfields.html.tmpl
index acbab223b..810808994 100644
--- a/template/en/default/admin/params/bugfields.html.tmpl
+++ b/template/en/default/admin/params/bugfields.html.tmpl
@@ -75,4 +75,8 @@
   clear_requests_on_close => "Clear all unanswered flag requests when changing bug status to CLOSED",
 
   unauth_bug_details => "Show product name to the user in Unauthorized message if he doesn't have access to bug.",
+
+  comment_line_length => "Symbols in one \"line\" whithout linebreaks.",
+
+  preview_comment_lines => "If comment's count of lines (one line is &lt;comment_line_length&gt; symbols or linebreaked line) is greater this value preview of text is shown.",
 } %]
diff --git a/template/en/default/bug/format_comment.txt.tmpl b/template/en/default/bug/format_comment.txt.tmpl
index 589d18027..49b94714d 100644
--- a/template/en/default/bug/format_comment.txt.tmpl
+++ b/template/en/default/bug/format_comment.txt.tmpl
@@ -31,7 +31,7 @@
   #%]
 
 [% IF comment.type == constants.CMT_DUPE_OF %]
-X[% comment.body %]
+X[% comment.body(preview) %]
 
 *** This [% terms.bug %] has been marked as a duplicate of [% terms.bug %] [%+ comment.extra_data %] ***
 [% ELSIF comment.type == constants.CMT_HAS_DUPE %]
@@ -39,7 +39,7 @@ X[% comment.body %]
 [% ELSIF comment.type == constants.CMT_POPULAR_VOTES %]
 *** This [% terms.bug %] has been confirmed by popular vote. ***
 [% ELSIF comment.type == constants.CMT_MOVED_TO %]
-X[% comment.body %]
+X[% comment.body(preview) %]
 
 [%+ terms.Bug %] moved to [% Param("move-to-url") %].
 If the move succeeded, [% comment.extra_data %] will receive a mail containing
@@ -53,7 +53,7 @@ Created attachment [% comment.extra_data %]
 [% END %]
 [%+ comment.attachment.description %]
 
-[%+ comment.body %]
+[%+ comment.body(preview) %]
 [% ELSIF comment.type == constants.CMT_ATTACHMENT_UPDATED %]
 Comment on attachment [% comment.extra_data %]
 [% IF is_bugmail %]
@@ -61,5 +61,5 @@ Comment on attachment [% comment.extra_data %]
 [% END %]
 [%+ comment.attachment.description %]
 
-[%+ comment.body %]
+[%+ comment.body(preview) %]
 [% END %]