Can't call method "label" on an undefined value

I found this page in Japanese and translated it via Google with this interesting result (page is CC licensed:

Can't call method "label" on an undefined value for error

After backing up the entire Movable Type 4.2 blog, and then re-exported, you may get the above error when you rebuild.

I, the above error "Rebuild site" we have been experiencing in the middle of the record suffered so much as a memorandum.

If the prescription is for good people with the same worries. .

Whether the law should deal with this is completely unknown. The error was avoided only state a result on a dead look. So now we can not have a description Gomennasai fundamental avoidance behavior.

The installation directory under / lib / MT / Entry.pm to edit.

my @ cats = sort ($ a-> label cmp $ b-> label) @ $ cats

Rewrite it as follows,

my @ cats; 
eval ( 'my @ cats = sort ($ a-> labelstrong> c mp $ b-> label) @ $ cats');

Complete.

No problems so far, we have spent.

Instead of doing this, I'm trying to track down the entry which has an incorrect category applied to it.

Also, I have to wonder about the Creative Commons license referenced above. It includes the "No Derivative" restriction - do you think that includes translations?