public domain code

Hi, I am thinking of contributing some code to an existing PEAR module. The code is currently in the public domain and the "owners" are happy for it to stay that way rather than being put under the LGPL or similar license. owners == people who originally paid for the code development. They no longer have an interest in the code. My understanding from fsf.org is that public domain code is plug-compatible with any other, however I thought I'd check with the crew here first. Of course I know it's possible to re-license public domain code. I'd rather not do that but if I have to then I will. -- Del