php-4.0.2, --with-imap and imap_utf7_encode() problem

Hello; A search of the archives and FAQ didn't turn this up as something everybody's talking about. I found a couple of hits, but the indicated that imap may be missing, which shouldn't be the case. Having compiled the php4 module for apache, an application (horde/imp2.2.0, if that matters) keeps telling me this: Fatal error: Call to undefined function: imap_utf7_encode() in /usr/share/horde/lib/horde.lib on line 440 I've compiled apache 1.3.12, added php-4.0.2 configured with ./configure --with-mysql \ --with-imap=../imap-4.5\ --with-apxs=/p/web/apache/current/bin/apxs (The imap path above is UW's imap-4.5.tar.Z, containing a successfully compiled c-client.a linked to lib/libc-client.a, and include files under include/*.h.) No errors occurred at any point in compilation, imap seems to get included, and normal PHP title pages work fine; only when PHP tries to use the imap function, we wind up with the error. Is the imap library not found, after all? PHP's compile didn't complain, and it's static, so we shouldn't have to worry about it afterward, right? What gives? (The same imp/horde combination worked perfectly with Debian's apache-ssl + php3 packages, but I need to update the server, so that's not an option.) I'd appreciate any pointers. A lot. Thanks; //ebu