The only way that i know of to password protect your phone until a decent patch comes out is to use a flash menu with password protection.. an example of this is the iPhone theme that i attatched to this post
The ".thm" file goes in your theme folder on your memory stick or in your phone but the ".swf" file has to be uploaded to "/tpa/preset/system/desktop/flash".
This can be done via FSX function in XS++ v3.1
Originally, the password for your messages and file manager are both "1111"
However, i edited the .swf file to allow an 2x 8 digit numerical passwords of your choice..
..Just edit the .swf file yourself or let me know what passwords you would like for which part and i will gladly create one for you :D