Index: add-textdomain.php
===================================================================
--- add-textdomain.php	(revision 20449)
+++ add-textdomain.php	(working copy)
@@ -69,12 +69,18 @@
 			} elseif (')' == $token) {
 				--$parens_balance;
 				if ($in_func && 0 == $parens_balance) {
-					$token = $found_domain? ')' : ", '$domain')";
+					$token = $found_domain? ')' : ", '$domain' )";
 					$in_func = false;
 					$args_started = false;
 					$found_domain = false;
 				}
 			}
+            // http://core.trac.wordpress.org/ticket/21616
+            // fix opening parentheses missing space character
+            if ($prev_token == '(' && $token !== ' ') {
+                $token = ' ' . $token;
+            }
+            $prev_token = $token;
 			$this->process_token($token, $inplace);
 		}