can you try replacing the following line in modules/twitter.module.php ?
Line 829: $tweetText = preg_replace("@(https?://([-\w\.]+[-\w])+(:\d+)?(/([\w/_\.#-]*(\?\S+)?[^\.\s])?)?)@", '', $tweet->text);
becomes
$tweetText = preg_replace("@(https?://([-\w\.]+[-\w])+(:\d+)?(/([\w/_\.#-]*(\?\S+)?[^\.\s])?)?)@u", '', $tweet->text);
can you try replacing the following line in modules/ twitter. module. php ?
Line 829: "@(https? ://([-\ w\.]+[- \w])+(: \d+)?(/ ([\w/_\ .#-]*(\ ?\S+)?[ ^\.\s]) ?)?)@", '', $tweet->text);
$tweetText = preg_replace(
becomes
$tweetText = preg_replace( "@(https? ://([-\ w\.]+[- \w])+(: \d+)?(/ ([\w/_\ .#-]*(\ ?\S+)?[ ^\.\s]) ?)?)@u" , '', $tweet->text);