diff --git a/hawk/lib/hawk-mtx.h b/hawk/lib/hawk-mtx.h
index e7dad337..36cb6722 100644
--- a/hawk/lib/hawk-mtx.h
+++ b/hawk/lib/hawk-mtx.h
@@ -41,8 +41,8 @@ typedef struct hawk_mtx_t hawk_mtx_t;
 	typedef unsigned long hawk_mtx_hnd_t;
 
 #elif defined(__DOS__)
-	/* not implemented */
-#	error not implemented
+	/* not implemented. define it to a fake type */
+	typedef hawk_uintptr_t hawk_mtx_hnd_t;
 
 #elif defined(__BEOS__)
 	/* typedef int32 sem_id; 
@@ -52,7 +52,8 @@ typedef struct hawk_mtx_t hawk_mtx_t;
 #else
 
 #	if (HAWK_SIZEOF_PTHREAD_MUTEX_T == 0)
-#		error unsupported
+		/* no mutex support. just define it to an integer type to make the compiler happy */
+		typedef hawk_uintptr_t hawk_mtx_hnd_t;
 
 #	elif (HAWK_SIZEOF_PTHREAD_MUTEX_T == HAWK_SIZEOF_INT)
 #		if defined(HAWK_PTHREAD_MUTEX_T_IS_SIGNED)
diff --git a/hawk/lib/hawk-prv.h b/hawk/lib/hawk-prv.h
index 45fb2cf7..1b4abfb0 100644
--- a/hawk/lib/hawk-prv.h
+++ b/hawk/lib/hawk-prv.h
@@ -144,8 +144,20 @@ typedef struct hawk_tree_t hawk_tree_t;
 
 #else
 
-#	if !defined(HAVE___BUILTIN_MEMSET) || !defined(HAVE___BUILTIN_MEMCPY) || !defined(HAVE___BUILTIN_MEMMOVE) || !defined(HAVE___BUILTIN_MEMCMP)
-#	include <string.h>
+	/* g++ 2.95 had a problem with __builtin_memxxx functions:
+	 * implicit declaration of function `int HAWK::__builtin_memset(...)' */
+#	if defined(__cplusplus) && defined(__GNUC__) && (__GNUC__ <= 2)
+#		undef HAVE___BUILTIN_MEMSET
+#		undef HAVE___BUILTIN_MEMCPY
+#		undef HAVE___BUILTIN_MEMMOVE
+#		undef HAVE___BUILTIN_MEMCMP
+#	endif
+
+#	if !defined(HAVE___BUILTIN_MEMSET) || \
+        !defined(HAVE___BUILTIN_MEMCPY) || \
+        !defined(HAVE___BUILTIN_MEMMOVE) || \
+        !defined(HAVE___BUILTIN_MEMCMP) 
+#		include <string.h>
 #	endif
 
 #	if defined(HAVE___BUILTIN_MEMSET)
diff --git a/hawk/lib/mtx.c b/hawk/lib/mtx.c
index 64c9da2f..bd46bd2f 100644
--- a/hawk/lib/mtx.c
+++ b/hawk/lib/mtx.c
@@ -102,9 +102,13 @@ int hawk_mtx_init (hawk_mtx_t* mtx, hawk_gem_t* gem)
 	}
 
 #elif defined(__DOS__)
-#	error not implemented
-
+	/* nothing to implement */
 #else
+
+	#if (HAWK_SIZEOF_PTHREAD_MUTEX_T <= 0)
+		/* nothing to initialize as there is no actual mutex support */
+	#else
+
 	/*
 	hawk_ensure (pthread_mutexattr_init (&attr) == 0);
 	if (pthread_mutexattr_settype (&attr, type) != 0) 
@@ -127,6 +131,8 @@ int hawk_mtx_init (hawk_mtx_t* mtx, hawk_gem_t* gem)
 			return -1;
 		}
 	}
+
+	#endif
 #endif
 
 	return 0;
@@ -141,10 +147,14 @@ void hawk_mtx_fini (hawk_mtx_t* mtx)
 	DosCloseMutexSem (mtx->hnd);
 
 #elif defined(__DOS__)
-#	error not implemented
+	/* nothing to destroy as there is no mutex support */
 
 #else
+	#if (HAWK_SIZEOF_PTHREAD_MUTEX_T <= 0)
+	/* nothing to destroy as there is no actual mutex support */
+	#else
 	pthread_mutex_destroy ((pthread_mutex_t*)&mtx->hnd);
+	#endif
 #endif
 }
 
@@ -222,6 +232,9 @@ int hawk_mtx_lock (hawk_mtx_t* mtx, const hawk_ntime_t* waiting_time)
 	/* nothing to do */
 
 #else
+	#if (HAWK_SIZEOF_PTHREAD_MUTEX_T <= 0)
+		/* nothing to do as there is no actual mutex support */
+	#else
 
 	/* if pthread_mutex_timedlock() isn't available, don't honor the waiting time. */
 	#if defined(HAVE_PTHREAD_MUTEX_TIMEDLOCK)
@@ -256,6 +269,8 @@ int hawk_mtx_lock (hawk_mtx_t* mtx, const hawk_ntime_t* waiting_time)
 	#if defined(HAVE_PTHREAD_MUTEX_TIMEDLOCK)
 	}
 	#endif
+
+	#endif
 #endif
 
 	return 0;
@@ -284,6 +299,10 @@ int hawk_mtx_unlock (hawk_mtx_t* mtx)
 	/* nothing to do */
 
 #else
+	#if (HAWK_SIZEOF_PTHREAD_MUTEX_T <= 0)
+		/* nothing to do as there is no actual mutex support */
+	#else
+
 	int n;
 	n = pthread_mutex_unlock((pthread_mutex_t*)&mtx->hnd);
 	if (n != 0) 
@@ -291,6 +310,8 @@ int hawk_mtx_unlock (hawk_mtx_t* mtx)
 		hawk_gem_seterrnum (mtx->gem, HAWK_NULL, hawk_syserr_to_errnum(n));
 		return -1;
 	}
+
+	#endif
 #endif
 	return 0;
 }
@@ -317,6 +338,9 @@ int hawk_mtx_trylock (hawk_mtx_t* mtx)
 
 #else
 
+	#if (HAWK_SIZEOF_PTHREAD_MUTEX_T <= 0)
+		/* nothing to do as there is no actual mutex support */
+	#else
 	/* -------------------------------------------------- */
 	int n;
 	#if defined(HAVE_PTHREAD_MUTEX_TRYLOCK)
@@ -338,6 +362,7 @@ int hawk_mtx_trylock (hawk_mtx_t* mtx)
 		return -1;
 	}
 	/* -------------------------------------------------- */
+	#endif
 
 #endif
 	return 0;