fixed regression in CRM-11301, due to changes in 4.4

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* CRM-11301: Add / Edit Activity: create new contact option for With contact (target) field
  http://issues.civicrm.org/jira/browse/CRM-11301
Merge pull request #2029 from kurund/CRM-11301

fixed regression in CRM-11301, due to changes in 4.4