diff --git a/mozilla/editor/ui/composer/content/TextEditorAppShell.xul b/mozilla/editor/ui/composer/content/TextEditorAppShell.xul
index 79fbbe42980..626305198da 100644
--- a/mozilla/editor/ui/composer/content/TextEditorAppShell.xul
+++ b/mozilla/editor/ui/composer/content/TextEditorAppShell.xul
@@ -130,7 +130,7 @@ editor.xul has these - do we need them?
       <toolbarbutton id="newButton"/>
       <toolbarbutton id="openButton"/>
       <toolbarbutton id="saveButton"/>
-      <spacer class="separator_small"/>
+      <spacer class="separator-small"/>
       <toolbarbutton id="printButton"/>
       <toolbarbutton id="spellingButton"/>
       <spacer flex="1"/>
diff --git a/mozilla/themes/classic/editor/mac/textEditor.css b/mozilla/themes/classic/editor/mac/textEditor.css
index 658a26d0a38..025bd9a024c 100644
--- a/mozilla/themes/classic/editor/mac/textEditor.css
+++ b/mozilla/themes/classic/editor/mac/textEditor.css
@@ -22,6 +22,6 @@
 
 @namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul");
 
-.separator_small {
+.separator-small {
   width: 1em;
 }
diff --git a/mozilla/themes/classic/editor/win/textEditor.css b/mozilla/themes/classic/editor/win/textEditor.css
index 658a26d0a38..025bd9a024c 100644
--- a/mozilla/themes/classic/editor/win/textEditor.css
+++ b/mozilla/themes/classic/editor/win/textEditor.css
@@ -22,6 +22,6 @@
 
 @namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul");
 
-.separator_small {
+.separator-small {
   width: 1em;
 }