Index: wp-admin/plugin-editor.php
===================================================================
--- wp-admin/plugin-editor.php	(revision 24036)
+++ wp-admin/plugin-editor.php	(working copy)
@@ -185,7 +185,9 @@
 <?php
 	foreach ( $plugins as $plugin_key => $a_plugin ) {
 		$plugin_name = $a_plugin['Name'];
-		if ( $plugin_key == $plugin )
+		$plugin_key_part = explode('/', $plugin_key);
+		$plugin_part = explode('/', $plugin);
+		if ( $plugin_key_part[0] == $plugin_part[0] )
 			$selected = " selected='selected'";
 		else
 			$selected = '';