forward porting url extension bugfix from branch

docs/changelog/7.x.x.txt

@@ -12,6 +12,8 @@
 7.4.18
  - fix: Auto Request Commit setting creates extra version tag if asset uses
    requestAutoCommit
+ - fix: URL extensions (perlDreamer Consulting, LLC.)
+     http://www.plainblack.com/bugs/tracker/url-extensions
  - fix: Some urls cause an asset to be inaccessible after creation/editing (perlDreamer Consulting, LLC.)
      http://www.plainblack.com/bugs/tracker/some-urls-cause-an-asset-to-be-inaccessible-after-creation/editing
  - fix: Secondary Admin can create user with Admin Privilege (IRC:blacksilver)

lib/WebGUI/Asset.pm

@@ -592,8 +592,9 @@ sub fixUrl {
 
 	# add automatic extension if we're supposed to
 	if ($self->session->setting->get("urlExtension") ne "" #don't add an extension if one isn't set
-		&& !($url =~ /\./) #don't add an extension of the url already contains a dot
-		&& $self->get("url") eq $self->getId # only add it if we're creating a new url
+		&& !($url =~ /\./)                   # don't add an extension of the url already contains a dot
+		&& lc($self->get("url")) eq lc($self->getId) # only add it if we're creating a new url
+        && $url ne lc($self->getId)          # but don't assign it the original time
 		) {
 		$url .= ".".$self->session->setting->get("urlExtension");
 	}