diff --git a/Misc/NEWS b/Misc/NEWS
index c6092bc..691774f 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -186,6 +186,9 @@
 Extension Modules
 -----------------
 
+- Bug #1290333: Added a workaround for cjkcodecs' _codecs_cn build
+  problem on AIX.
+
 - Bug #869197: os.setgroups rejects long integer arguments
 
 - Bug #1346533, select.poll() doesn't raise an error if timeout > sys.maxint
diff --git a/Modules/cjkcodecs/_codecs_cn.c b/Modules/cjkcodecs/_codecs_cn.c
index ac36b64..9a885bb 100644
--- a/Modules/cjkcodecs/_codecs_cn.c
+++ b/Modules/cjkcodecs/_codecs_cn.c
@@ -8,6 +8,14 @@
 #include "cjkcodecs.h"
 #include "mappings_cn.h"
 
+/**
+ * hz is predefined as 100 on AIX. So we undefine it to avoid
+ * conflict against hz codec's.
+ */
+#ifdef _AIX
+#undef hz
+#endif
+
 #define GBK_PREDECODE(dc1, dc2, assi) \
 	if ((dc1) == 0xa1 && (dc2) == 0xaa) (assi) = 0x2014; \
 	else if ((dc1) == 0xa8 && (dc2) == 0x44) (assi) = 0x2015; \