You didn't say anything about a data DLL<g>, in that case no. As to the variable there generally is still an assignment someplace that you can find. Unless of course the developer knows about this and tries to make the assignment character by character at several different point in the program. Finally if an algorithm is used to set the variable value it will be most difficult. A sure fire way (if you have the patience) is to load the application and then crash it getting a memory dump, the password can be seen in the dump. I have not tried this with a data DLL, let me know if it works.
HTH