Well, not really. The biggest problem is: if OpenACS' implementation of search is based on psl and pls gets ditched by AOL (and the fact that they're only providing RedHat 5.2 rpms, which, among others, leaves out Debian and probably others out of the equation, doesn't really give me a lot of confidence in their countinuing support) in a few months the whole work would get obsolete because old binaries would no longer work and you couldn't fix them yourself.
However, as the (real) Free Software philosophy goes: you've got the source (to OpenACS) and there is nothing that can stop you to provide OpenACS search interface for pls.
