A) You are using a very old version of FileMaker, thank you for telling us that or you might have gotten advice that doesn't work with a version that old.
B) There are several ways that you might be using the Web here. Please describe how you are setting it up.
C) I get that it doesn't work via the "web", but exactly HOW does it fail? User can't enter notes into the field? Can't find a notes field to edit? They enter notes and they disappear? Or something else maybe?
Also, what FileMaker 11 web technology are you using here? Instant Web Publishing? PHP?