diff --git a/Bugzilla/DB/Mysql.pm b/Bugzilla/DB/Mysql.pm
index bb3ccfb88..f00e530e0 100644
--- a/Bugzilla/DB/Mysql.pm
+++ b/Bugzilla/DB/Mysql.pm
@@ -179,8 +179,7 @@ sub sql_fulltext_search
     my ($self, $column, $text) = @_;
 
     # stem text
-    my $lang = LANG_FULL_ISO->{lc(Bugzilla->params->{stem_language}||'')} || 'en';
-    $text = stem_text($text, $lang);
+    $text = stem_text($text, Bugzilla->params->{stem_language});
 
     # quote un-quoted compound words
     my @words = quotewords('[\s()]+', 'delimiters', $text);
diff --git a/Bugzilla/DB/Pg.pm b/Bugzilla/DB/Pg.pm
index db4d0b9e3..55474f7e7 100644
--- a/Bugzilla/DB/Pg.pm
+++ b/Bugzilla/DB/Pg.pm
@@ -44,7 +44,7 @@ package Bugzilla::DB::Pg;
 use strict;
 
 use Bugzilla::Error;
-use Bugzilla::Constants qw(LANG_ISO_FULL);
+use Bugzilla::Constants qw(LANG_ISO_FULL LANG_FULL_ISO);
 use DBD::Pg;
 
 # This module extends the DB interface via inheritance
@@ -189,13 +189,15 @@ sub sql_fulltext_search
     my $self = shift;
     my ($column, $text) = @_;
     $text = $self->quote($text);
+    my $lang = lc(Bugzilla->params->{stem_language} || 'en');
+    $lang = LANG_ISO_FULL->{$lang} || 'english' if !LANG_FULL_ISO->{$lang};
     # Try to_tsquery, and use plainto_tsquery if the syntax is incorrect
     # FIXME reporting query parse errors to user would be useful here
-    eval { $self->do("SELECT to_tsquery($language$text)") };
+    eval { $self->do("SELECT to_tsquery('$lang',$text)") };
     my $op = $@ ? 'plainto_tsquery' : 'to_tsquery';
     return (
-        "($column \@\@ $op($language$text))",
-        "(ts_rank($column, $op($language$text)))",
+        "($column \@\@ $op('$lang',$text))",
+        "(ts_rank($column, $op('$lang',$text)))",
     );
 }
 
@@ -204,7 +206,8 @@ sub quote_fulltext
 {
     my $self = shift;
     my ($a) = @_;
-    my $lang = LANG_ISO_FULL->{Bugzilla->params->{stem_language}} || 'english';
+    my $lang = lc(Bugzilla->params->{stem_language}||'en');
+    $lang = LANG_ISO_FULL->{$lang} || 'english' if !LANG_FULL_ISO->{$lang};
     return "to_tsvector('$lang',".$self->quote($a).")";
 }
 
diff --git a/Bugzilla/Util.pm b/Bugzilla/Util.pm
index a0e8ae880..94661d1e4 100644
--- a/Bugzilla/Util.pm
+++ b/Bugzilla/Util.pm
@@ -740,6 +740,7 @@ sub stem_text
     my ($text, $lang, $allow_verbatim) = @_;
     return '' if !defined $text || $text =~ /^\s*$/so;
     return $text if !$INC{'Lingua/Stem/Snowball.pm'};
+    $lang = lc($lang || 'en');
     $lang = LANG_FULL_ISO->{$lang} || 'en' if !LANG_ISO_FULL->{$lang};
     Encode::_utf8_on($text) if Bugzilla->params->{utf8};
     # CustIS Bug 66033 - _ is wanted to also be a delimiter