Please try using this CVS snapshot:

  http://snaps.php.net/php4-STABLE-latest.tar.gz
 
For Windows:
 
  http://snaps.php.net/win32/php4-win32-STABLE-latest.zip


And if the error persists, check config.log for the actual
reason why the test fails..

No better. Below is the tail of config.log.   This shows (correctly) an undefined reference to ssl_onceonlyinit()
which should cause it to eventually not define HAVE_IMAP_SSL
and configure should not complain about the lack of 
--with-imap-ssl=pathname

Ian D
---
configure:36224: checking whether SSL libraries are needed for c-client
configure:36353: gcc -o conftest -g -O2  -D_POSIX_PTHREAD_SEMANTICS -R/opt/local/lib -R/usr/ucblib -L/usr/ucblib -R/opt/local/lib/gcc-lib/sparc-sun-solaris2.7/2.95.2 -L/opt/local/lib/gcc-lib/sparc-sun-solaris2.7/2.95.2 -R/import/src/www/EKCapache/sparc_sol2.7/imap-2002b/c-client -L/import/src/www/EKCapache/sparc_sol2.7/imap-2002b/c-client conftest.c -L/import/src/www/EKCapache/sparc_sol2.7/imap-2002b/c-client -lc-client -lcrypt -lpam -lresolv -lm -lsocket  -lgcc 1>&5
/var/tmp/cc1WsREP.o: In function `main':
/import/src/www/EKCapache/sparc_sol2.7/php4-STABLE-200304290130/configure:36347: undefined reference to `ssl_onceonlyinit'
collect2: ld returned 1 exit status
configure: failed program was:
#line 36328 "configure"
#include "confdefs.h"

    void mm_log(void){}
    void mm_dlog(void){}
    void mm_flags(void){}
    void mm_fatal(void){}
    void mm_critical(void){}
    void mm_nocritical(void){}
    void mm_notify(void){}
    void mm_login(void){}
    void mm_diskerror(void){}
    void mm_status(void){}
    void mm_lsub(void){}
    void mm_list(void){}
    void mm_exists(void){}
    void mm_searched(void){}
    void mm_expunged(void){}
    char ssl_onceonlyinit();
    int main() {
      ssl_onceonlyinit();
      return 0;
    }

This bug has been fixed in CVS.

In case this was a PHP problem, snapshots of the sources are packaged
every three hours; this change will be in the next snapshot. You can
grab the snapshot at http://snaps.php.net/.
 
In case this was a documentation problem, the fix will show up soon at
http://www.php.net/manual/.

In case this was a PHP.net website problem, the change will show
up on the PHP.net site and on the mirror sites in short time.
 
Thank you for the report, and for helping us make PHP better.