Bug 542570 - Directory Server port number is not validated in the beginning.
    
    https://bugzilla.redhat.com/show_bug.cgi?id=542570
    Resolves: bug 542570
    Bug Description: Directory Server port number is not validated in the beginning.
    Fix Description: The code has been modified to validate the port value from the
    beginning of the string to the end to ensure that it only contains digits and to
    generate the appropriate error message.
    Reviewed by: rmeggins (and pushed)
    (cherry picked from commit a7b2cdc8c3ee5fcc23155d791cafc48f554008f2)