Argument length issue: a Services Browser issue or an overall Services argument processing issue?

Is there a limit on the length of string arguments passed through the services browser? How about the length of a string argument for a services method called outside the Services Browser?

I have a method with a string argument that is an external URL. Trying a test via the Services Browser where the url is around 150 characters long, I am only getting the first 128 characters of the string in my services method.

I hope this is a Services Browser issue only, and would like some means of raising that max string length as well.

Are there any controls for the length of a string argument? Is this 128 character limit in place outside the Services Browser?