URL with unicode signs breaks down trackable urls

Method CRM_Mailing_BAO_Mailing->getPatterns() is used for extracting urls from content of mailing. The problem occurs when url contains any unicode sign.

Example:
localhost:8003/civicrm/?var1=państewko - where ń is special character in unicode

results in civicrm_mailing_trackable_url.url:
two urls!
http://localhost:8003/civicrm/?var1=pa
href="http://localhost:8003/civicrm/?var1=pa

after patch:
one valid url:
http://localhost:8003/civicrm/?var1=państewko

solution: add u modifier to regex pattern