diff --git a/Lib/irix5/CD.py b/Lib/irix5/CD.py
index 9dee8a18362..ad56561235e 100755
--- a/Lib/irix5/CD.py
+++ b/Lib/irix5/CD.py
@@ -14,7 +14,8 @@ CATALOG		= 5
 IDENT		= 6
 CONTROL		= 7
 
-##CDDA_DATASIZE	= 2352
+CDDA_DATASIZE	= 2352
+
 ##CDDA_SUBCODESIZE	= (sizeof(struct subcodeQ))
 ##CDDA_BLOCKSIZE	= (sizeof(struct cdframe))
 ##CDDA_NUMSAMPLES	= (CDDA_DATASIZE/2)
diff --git a/Lib/plat-irix5/CD.py b/Lib/plat-irix5/CD.py
index 9dee8a18362..ad56561235e 100755
--- a/Lib/plat-irix5/CD.py
+++ b/Lib/plat-irix5/CD.py
@@ -14,7 +14,8 @@ CATALOG		= 5
 IDENT		= 6
 CONTROL		= 7
 
-##CDDA_DATASIZE	= 2352
+CDDA_DATASIZE	= 2352
+
 ##CDDA_SUBCODESIZE	= (sizeof(struct subcodeQ))
 ##CDDA_BLOCKSIZE	= (sizeof(struct cdframe))
 ##CDDA_NUMSAMPLES	= (CDDA_DATASIZE/2)