(series 40) > 64 k warning but jar is just 63.3 ?

[ooooooo]

My midlet of 64 850 jar size (jad 160 bytes) generates on 7210 emulator "Jar file is too large to run on actual phone" message. It is just 63.3 kB -within limit.
I compared another midlet which is 63.6 and runs fine without such message.
Do you have any idea why?
Some clue might be that the first is 120 kB size unpacked , the later 90 kB, but why would this matter?

[canard_42]

Then the problem may come from the value of the MIDlet-Data-Size attribute, if you use it in your jad file. The value cannot be more than the max RMS size.

[ooooooo]

No, I don't use it.
I found out that the "too large" warning disappears when jar size gets below 62.5 kB. Unfortunately all is just already as squeezed and optimized as I could manage and I really need almost all of 64 kB