Index: /trunk/src/VBox/VMM/VMMAll/IEMAll.cpp
===================================================================
--- /trunk/src/VBox/VMM/VMMAll/IEMAll.cpp	(revision 51255)
+++ /trunk/src/VBox/VMM/VMMAll/IEMAll.cpp	(revision 51256)
@@ -10935,4 +10935,7 @@
 VMMDECL(VBOXSTRICTRC) IEMInjectTrpmEvent(PVMCPU pVCpu)
 {
+#ifndef IEM_IMPLEMENTS_TASKSWITCH
+    IEM_RETURN_ASPECT_NOT_IMPLEMENTED_LOG(("Event injection\n"));
+#else
     uint8_t     u8TrapNo;
     TRPMEVENT   enmType;
@@ -10946,4 +10949,5 @@
     TRPMResetTrap(pVCpu);
     return IEMInjectTrap(pVCpu, u8TrapNo, enmType, uErrCode, uCr2, cbInstr);
+#endif
 }
 
Index: /trunk/src/VBox/VMM/include/EMHandleRCTmpl.h
===================================================================
--- /trunk/src/VBox/VMM/include/EMHandleRCTmpl.h	(revision 51255)
+++ /trunk/src/VBox/VMM/include/EMHandleRCTmpl.h	(revision 51256)
@@ -278,7 +278,10 @@
 #ifdef VBOX_WITH_FIRST_IEM_STEP
             rc = VBOXSTRICTRC_VAL(IEMInjectTrpmEvent(pVCpu));
+            /* The following condition should be removed when IEM_IMPLEMENTS_TASKSWITCH becomes true. */
+            if (rc == VERR_IEM_ASPECT_NOT_IMPLEMENTED)
+                rc = emR3ExecuteInstruction(pVM, pVCpu, "EVENT: ");
 #else
             /* Do the same thing as VINF_EM_RAW_EMULATE_INSTR. */
-            rc = emR3ExecuteInstruction(pVM, pVCpu, "EMUL: ");
+            rc = emR3ExecuteInstruction(pVM, pVCpu, "EVENT: ");
 #endif
             break;