When Apple unveiled its new tablet earlier this month, the consensus seemed to be that it would continue to work with all iPad 2 Smart Covers. After all, the new iPad’s frontside dimensions are identical to its predecessors.

But apparently that isn’t the case. As noted by iLounge, the new iPad uses a slightly different magnet system that causes some newer Smart Covers, and similar third party magnet-driven cases, not to work properly…

“One of the two exceptions we noted was magnetic Smart Cover-like cases—ones with lids that were supposed to automatically lock and unlock the iPad’s screen. A small change by Apple means that some of the magnetic lids developed for the iPad 2 continue to work, while others don’t…

…Contrary to claims that the original iPad Smart Cover (released alongside the iPad 2 in March 2011) doesn’t work or works inconsistently with the new iPad, we’ve tested both leather and plastic versions of that Smart Cover with multiple third-generation iPads, and both work reliably…

…Reports on Apple’s Support Communities Forum, however, suggest that some people are getting new Smart Covers that aren’t working with new iPads, which is obviously concerning.”

The report goes on to suggest that new iPad buyers should hold off on purchasing Smart Cover-like cases until this issue gets worked out. If you are already experiencing problems, you can try contacting the case’s manufacturer.

Have you noticed any issues with your Smart Cover and your new iPad?