diff --git a/kernel/busses/i2c-i801.c b/kernel/busses/i2c-i801.c
index 49a5a31b..e1b52b61 100644
--- a/kernel/busses/i2c-i801.c
+++ b/kernel/busses/i2c-i801.c
@@ -51,6 +51,11 @@
 #include "version.h"
 #include "sensors_compat.h"
 
+/* 82801DB is undefined before kernel 2.4.19 */
+#ifndef PCI_DEVICE_ID_INTEL_82801DB_3
+#define PCI_DEVICE_ID_INTEL_82801DB_3      0x24c3
+#endif
+
 #ifdef I2C_FUNC_SMBUS_BLOCK_DATA_PEC
 #define HAVE_PEC
 #endif
diff --git a/kernel/busses/i2c-viapro.c b/kernel/busses/i2c-viapro.c
index 8af13b93..cc43286c 100644
--- a/kernel/busses/i2c-viapro.c
+++ b/kernel/busses/i2c-viapro.c
@@ -399,6 +399,11 @@ static void __devexit vt596_remove(struct pci_dev *pdev)
 	release_region(vt596_smba, 8);
 }
 
+/* 8233A is undefined before kernel 2.4.19 */
+#ifndef PCI_DEVICE_ID_VIA_8233A
+#define PCI_DEVICE_ID_VIA_8233A	0x3147
+#endif
+/* 8235 is undefined before kernel 2.4.20 */
 #ifndef PCI_DEVICE_ID_VIA_8235
 #define PCI_DEVICE_ID_VIA_8235	0x3177
 #endif