Microsoft IMAP servers respond with the wrong size

Question

I've noticed that the IMAP servers used for Outlook.com / Office365 seem to have (yet another) defect, this time, responding with the wrong size when the client requests it.

Thick mail clients don't seem to get bothered too much by this since they download the message and use that for the size, but this causes the size in webmail to all be reported incorrectly, based on the false information provided by the server. Here's an example:

a UID FETCH 184803 (RFC822.SIZE) 
* 24 FETCH (RFC822.SIZE 55906 UID 184803) 
a OK FETCH completed. 
a UID FETCH 184803 (RFC822) 
* 24 FETCH (RFC822 {12234}
<message follows> 

The respond to UID FETCH RFC822.SIZE is wrong, it should respond RFC822.SIZE 12234, as can be seen by the size literal when requesting the entire message, but for some reason, it responds RFC822.SIZE 55906. I tested a few messages and I can't find any obvious pattern or connection for what this arbitrary number has to do with the message. Other IMAP servers respond with the correct size. This isn't a defect I've noticed with any other IMAP servers.

Doesn't seem to be any way to report bugs to the Microsoft IMAP team, so if somebody with the appropriate permissions to do so is able to, that would be helpful!