--- linux-2.4.20/arch/i386/kernel/pci-irq_old.c	2002-11-28 15:53:09.000000000 -0800
+++ linux-2.4.20/arch/i386/kernel/pci-irq.c	2003-05-21 17:27:40.000000000 -0700
@@ -198,12 +198,27 @@
  */
 static int pirq_via_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
 {
-	return read_config_nybble(router, 0x55, pirq);
+    u8 x;
+
+    if ( pirq == 4 ) {
+        pci_read_config_byte(router, 0x57, &x);
+        return (x >> 4);
+    } else {
+        return read_config_nybble(router, 0x55, pirq);
+    }
 }
 
 static int pirq_via_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
 {
-	write_config_nybble(router, 0x55, pirq, irq);
+  	u8 x;
+
+    if ( pirq == 4 ) {
+        pci_read_config_byte(router, 0x57, &x);
+        x = (x & 0x0f) | (irq << 4);
+       	pci_write_config_byte(router, 0x57, x);
+    } else {
+        write_config_nybble(router, 0x55, pirq, irq);
+    }
 	return 1;
 }