This problem didn't exists in 3.0.15. But in 3.0.15 shared memory didn't work on Solaris 7 x86 (Bug #3621)
Configure line:
./configure  \
--with-oracle=/opt/oracle/product/8.0.4 \
--with-config-file-path=/usr/local/apache/conf \
--with-apxs=/usr/local/apache/bin/apxs \
--enable-magic-quotes=yes --disable-debug \
--enable-memory-limit=yes --enable-url-fopen-wrapper=no \
--enable-sysvsem=yes --enable-sysvshm=yes  \
--enable-track-vars=yes --with-system-regex

With this configuration code like this:
<?php
$semid = sem_get(0x123754);
sem_acquire($semid);
Echo "aaa";
sem_release($semid);
?>
gives "Document contains no data" and Bus error in error_log.

After some investigation, I've found the following:

From the man page for semctl on Solaris:
-------------------------------------------------------------
 The semctl() function provides a variety of  semaphore  con-
     trol  operations as specified by cmd. The fourth argument is
     optional,  depending  upon  the  operation   requested.   If
     required,  it  is of type  union semun, which must be expli-
     citly declared by the application program.

      union semun {
             int             val;
             struct semid_ds *buf;
             ushort_t        *array;
     } arg ;
-------------------------------------------------------------

There is already definition of this structure in semvsem.c:

#if !HAVE_SEMUN && defined(__GNU_LIBRARY__) && __GNU_LIBRARY__ == 6
union semun {
    int val;                    /* value for SETVAL */
    struct semid_ds *buf;       /* buffer for IPC_STAT, IPC_SET */
    unsigned short int *array;  /* array for GETALL, SETALL */
    struct seminfo *__buf;      /* buffer for IPC_INFO */
};
#undef HAVE_SEMUN
#define HAVE_SEMUN 1
#endif

  So, I changed the line

#if !HAVE_SEMUN && defined(__GNU_LIBRARY__) && __GNU_LIBRARY__ == 6
with
#if !HAVE_SEMUN

 and recompiled php with union semun defined - it compiled smoothly,
and worked on Solaris 7 [Sun|x86].

  The same problem exists in PHP4 tree.