Validator for custom fields of type 'URL' is too restrictive

Custom field of type 'URL' doesn't accept following URLs, for example:

testdirector:host:port/qcbin,TRADING,Forklift,maxim;2:20

Error: 'Not a valid URL' upon form submission.

Albeit not commonly looking, the above URL should be considered valid according to RFC 1738 (Uniform Resource Locators (URL)).

"In general, URLs are written as follows:

<scheme>:<scheme-specific-part>

A URL contains the name of the scheme being used (<scheme>) followed
by a colon and then a string (the <scheme-specific-part>) whose
interpretation depends on the scheme."

http://www.ietf.org/rfc/rfc1738.txt

The above URLs are produced by HP QualityCenter software and we want to add link issues from Jira to it.