diff --git a/cpu/arm920t/Makefile b/cpu/arm920t/Makefile
index e02bc6a..cbb13b2 100644
--- a/cpu/arm920t/Makefile
+++ b/cpu/arm920t/Makefile
@@ -26,10 +26,12 @@
 LIB	= $(obj)lib$(CPU).a
 
 START	= start.o
-COBJS	= cpu.o interrupts.o
 
-SRCS	:= $(START:.o=.S) $(SOBJS:.o=.S) $(COBJS:.o=.c)
-OBJS	:= $(addprefix $(obj),$(COBJS) $(SOBJS))
+COBJS-y	+= cpu.o
+COBJS-$(CONFIG_USE_IRQ)	+= interrupts.o
+
+SRCS	:= $(START:.o=.S) $(SOBJS:.o=.S) $(COBJS-y:.o=.c)
+OBJS	:= $(addprefix $(obj),$(COBJS-y) $(SOBJS))
 START	:= $(addprefix $(obj),$(START))
 
 all:	$(obj).depend $(START) $(LIB)