CTRL+P is the default ``force'' character, used to tell tip(1) that the next character is literal data. You can set the force character to any other character with the ~s escape, which means ``set a variable''.
Type ~sforce=single-char followed by a newline. single-char is any single character. If you leave out single-char, then the force character is the nul character, which you can get by typing CTRL+2 or CTRL+SPACE. A pretty good value for single-char is SHIFT+CTRL+6, which I have seen only used on some terminal servers.
You can have the force character be whatever you want by specifying the following in your $HOME/.tiprc file: