TFTP block with filename 6 char lenght

Does anyone else have problems with TFTP over Mikrotik RouterOS >6.15 with filename 6 char lenght?

The problem is still at 6.23 and looks like is really funny since with 5 or 7 char filename there is no problems. Could it be some funny exception since we use TFTP for programming our devices (uBoot and uImage)?

What seems to be an error? Do you receive error message when you try to configure tftp or when you download something?

Getting just timeout.

Over the weekend I have redoing upgrade version by version from 6.15 up. After upgrade from 6.18->6.19 problem come up. So the problem is from version 6.19 up. Any changes on TFTP that is not in CHANGELOG? otherwise I would guess that there is problem at firewall part!

PS: :cry: getting little annoyed with this problem :imp:
Putty2.png