weblogic + apex_040200 <Error> <Default> <BEA-000000> <The URI is not well-formed

We are using weblogic plus ápex to replace our OAS application server but in some pages we are getting an error when an special carácter such as # is used inside a text that is submited to the next page.

when we submit the information we get an error 500 message on the page and by looking at the server.out log we get

The URI is not well-formed, reason: ilegal carácter in fragment at position

but in our oas we do not get this error and the string is passed to the next page although cutted at the special carácter.