Index: theme-editor.php
===================================================================
--- theme-editor.php	(revision 18578)
+++ theme-editor.php	(working copy)
@@ -230,7 +230,7 @@
 		<div id="documentation" class="hide-if-no-js">
 		<label for="docs-list"><?php _e('Documentation:') ?></label>
 		<?php echo $docs_select; ?>
-		<input type="button" class="button" value=" <?php esc_attr_e( 'Lookup' ); ?> " onclick="if ( '' != jQuery('#docs-list').val() ) { window.open( 'http://api.wordpress.org/core/handbook/1.0/?function=' + escape( jQuery( '#docs-list' ).val() ) + '&amp;locale=<?php echo urlencode( get_locale() ) ?>&amp;version=<?php echo urlencode( $wp_version ) ?>&amp;redirect=true'); }" />
+		<input type="button" class="button" value=" <?php esc_attr_e( 'Lookup' ); ?> " onclick="if ( '' != jQuery('#docs-list').val() ) { window.open( '<?php echo esc_url( apply_filters( 'documentation_url', 'http://api.wordpress.org/core/handbook/1.0/?function=', $theme, $file ) ); ?>' + escape( jQuery( '#docs-list' ).val() ) + '&amp;locale=<?php echo urlencode( get_locale() ) ?>&amp;version=<?php echo urlencode( $wp_version ) ?>&amp;redirect=true'); }" />
 		</div>
 	<?php } ?>