Without seeing your code, it's going to be hard to give you an accurate answer. If you could provide a link to where your code resides, you might get some better responses.
A couple of things to look for however:
1.) Make sure each form element has a unique name. This can be overcome depending on what server side scripting you are using, but this could be the cause.
2.) Make sure you are using a method of post. Historically, a method of get has been limited to a maximum of 256 characters. I'm not sure if Safari has such a limitation, but some browsers will, and your get string will be cut at 256 characters.
Of course, the possibility exists that the problem is not in the html code itself, but in whatever activates on your action (ie - your server side script).
Dennis
