diff --git a/libjava/ChangeLog b/libjava/ChangeLog
index c7536be7429..3cb973189f3 100644
--- a/libjava/ChangeLog
+++ b/libjava/ChangeLog
@@ -1,3 +1,8 @@
+1999-07-12  Tom Tromey  <tromey@cygnus.com>
+
+	* java/lang/mprec.h: Protect definition of uint32_t with #ifndef
+	_UINT32_T.
+
 1999-07-07  Andrew Haley  <aph@cygnus.com>
 
         * include/i386-signal.h (MAKE_THROW_FRAME): Advance EIP by two
diff --git a/libjava/java/lang/mprec.h b/libjava/java/lang/mprec.h
index 7989075aac3..fbfba4c3ba0 100644
--- a/libjava/java/lang/mprec.h
+++ b/libjava/java/lang/mprec.h
@@ -61,7 +61,13 @@ typedef u_int32_t uint32_t;
 #if !defined HAVE_BSD_INT32_DEFINED && !defined HAVE_INT32_DEFINED
 // FIXME -- this could have problems with systems that don't define SI to be 4
 typedef int int32_t __attribute__((mode(SI)));
+
+/* This is a blatant hack: on Solaris 2.5, pthread.h defines uint32_t
+   in pthread.h, which we sometimes include.  We protect our
+   definition the same way Solaris 2.5 does, to avoid redefining it.  */
+#  ifndef _UINT32_T
 typedef unsigned int uint32_t __attribute__((mode(SI)));
+#  endif
 #endif
 
   /* These typedefs are true for the targets running Java. */