Nope. 1997 37-3 changed to J-Magnum frame and rated the gun .38 Spl. +P. 36-9 in August 1996 also changed to J-Magnum frame and .38 Spl. +P rating. All current production J Frames, regardless of caliber, are built on the J-Magnum frame.S&W is still making the Model 36/37 non-magnum j-frame. The frames may be leftovers, but have nothing to do with S&W's j-magnum Model 60s or 640s.
There is speculation that these are either leftovers or cancels from a foreign contract run, or that they have been assembled from left over parts. Either way, they're new guns without locks!