RFC 2616 (Hypertext Transfer Protocol HTTP/1.1) section 3.2.1 says
The HTTP protocol does not place any a priori limit on the length of a URI. Servers MUST be able to handle the URI of any resource they serve, and SHOULD be able to handle URIs of unbounded length if they provide GET-based forms that could generate such URIs. A server SHOULD return 414 (Request-URI Too Long) status if a URI is longer than the server can handle (see section 10.4.15).
Note: Servers ought to be cautious about depending on URI lengths above 255 bytes, because some older client or proxy implementations might not properly support these lengths.
But since GET resquest parameters names and values are embeded in the input url, and the input parameters of the post section
are located in the body section of the input xml, some problem may occurs with older browser with some request, since they limit
url to 255,512 or 1024 characters.