--- linux-2.6.25.3.old/drivers/misc/thinkpad_acpi.c	2008-05-12 11:43:16.000000000 +0200
+++ linux-2.6.25.3/drivers/misc/thinkpad_acpi.c	2008-05-16 11:20:48.000000000 +0200
@@ -6072,7 +6072,8 @@
 		remove_proc_entry(TPACPI_PROC_DIR, acpi_root_dir);
 
 	kfree(thinkpad_id.bios_version_str);
-	kfree(thinkpad_id.ec_version_str);
+	if (thinkpad_id.ec_version_str)	
+	      	kfree(thinkpad_id.ec_version_str);
 	kfree(thinkpad_id.model_str);
 }