this happened to me. I was in a previous version and I was in survival mode.
I had stone sword in my hand when I logged out. when I logged in on 13w25c, I changed to creative mode then I couldn't break blocks with any stone sword in any world in creative.
MC-18562
can't break blocks in creative
Resolved
Duplicate
0
A M
(Unassigned)
Unconfirmed
Snapshot 13w25c
Retrieved
Duplicate of MC-18368, please use the search function to see if your bug has already been submitted. Currently over 57% of tickets are being closed as duplicate.