diff --git a/c/src/lib/libcpu/powerpc/ChangeLog b/c/src/lib/libcpu/powerpc/ChangeLog
index f10c2e24a4..fb92f1377f 100644
--- a/c/src/lib/libcpu/powerpc/ChangeLog
+++ b/c/src/lib/libcpu/powerpc/ChangeLog
@@ -1,3 +1,9 @@
+2007-12-11	Till Straumann <strauman@slac.stanford.edu>
+
+	* new-exceptions/bspsupport/irq.c: enable/disable
+	irq at PIC if an initial handler is present/absent
+	(reproduce traditional semantics).
+
 2007-12-10	Till Straumann <strauman@slac.stanford.edu>
 
 	* new-exceptions/e500_raw_exc_init.c: map DEC
diff --git a/c/src/lib/libcpu/powerpc/new-exceptions/bspsupport/irq.c b/c/src/lib/libcpu/powerpc/new-exceptions/bspsupport/irq.c
index ed73936ecc..7a154e2195 100644
--- a/c/src/lib/libcpu/powerpc/new-exceptions/bspsupport/irq.c
+++ b/c/src/lib/libcpu/powerpc/new-exceptions/bspsupport/irq.c
@@ -346,6 +346,12 @@ int BSP_rtems_irq_mngt_set(rtems_irq_global_settings* config)
 			if (vchain->on)
               vchain->on(vchain);
 		}
+		if ( vchain != &rtems_hdl_tbl[i] ) {
+			/* at least one handler registered */
+			BSP_enable_irq_at_pic(i);
+		} else {
+			BSP_disable_irq_at_pic(i);
+		}
 	}
 
     rtems_interrupt_enable(level);