diff --git a/sim/mips/ChangeLog b/sim/mips/ChangeLog
index 53dc86c317377571d4020cc1f490e12814c60fd6..3d795571b4721f42d90c1f3f375a299ac4718538 100644
--- a/sim/mips/ChangeLog
+++ b/sim/mips/ChangeLog
@@ -1,3 +1,9 @@
+2004-05-11  Maciej W. Rozycki  <macro@ds2.pg.gda.pl>
+
+	* mips/interp.c (decode_coproc): Sign-extend the address retrieved 
+	from COP0_BADVADDR.
+	* mips/sim-main.h (COP0_BADVADDR): Remove a cast.
+
 2004-04-10  Chris Demetriou  <cgd@broadcom.com>
 
 	* sb1.igen (DIV.PS, RECIP.PS, RSQRT.PS, SQRT.PS): New.
diff --git a/sim/mips/interp.c b/sim/mips/interp.c
index f8c14c89ca9f30f6b5976bfe6471a29c987cd45e..043d76d10d3db8b73aeec8c28a1ab25dc0f8ef4b 100644
--- a/sim/mips/interp.c
+++ b/sim/mips/interp.c
@@ -2102,7 +2102,7 @@ decode_coproc (SIM_DESC sd,
 	      case 8:
 		/* 8 = BadVAddr            R4000   VR4100  VR4300 */
 		if (code == 0x00)
-		  GPR[rt] = COP0_BADVADDR;
+		  GPR[rt] = (signed_word) (signed_address) COP0_BADVADDR;
 		else
 		  COP0_BADVADDR = GPR[rt];
 		break;
diff --git a/sim/mips/sim-main.h b/sim/mips/sim-main.h
index 96a86e9c549f5c53f4071578e21d73b5456c2239..10ddbf24528cb8071f50418930a7de88fb962301 100644
--- a/sim/mips/sim-main.h
+++ b/sim/mips/sim-main.h
@@ -383,7 +383,7 @@ struct _sim_cpu {
 #define NR_COP0_GPR	32
   unsigned_word cop0_gpr[NR_COP0_GPR];
 #define COP0_GPR	((CPU)->cop0_gpr)
-#define COP0_BADVADDR ((unsigned32)(COP0_GPR[8]))
+#define COP0_BADVADDR	(COP0_GPR[8])
 
   /* While space is allocated for the floating point registers in the
      main registers array, they are stored separatly.  This is because