Maybe it is time for TC 7 to correct it?

Hi. I am in the process of modifying DiskDirExtended to support > 4GB files.
I found strange behaviour of TC when the plugin's reported file size (using UnpSize and UnpSizeHigh of tHeaderDataEx) is:
4294967295 (0xFFFF FFFF) the file size is displayed as [face=courier]?[/face]
4294967294 (0xFFFF FFFE) the file size is not displayed at all
For all other file sizes (that I tried, not for all 2^64 possibilities

4294967293 (0xFFFF FFFD)
4294967296 (0x1 0000 0000)
8589934591 (0x1 FFFF FFFF)
To be fair, the two mentioned file sizes (4294967295 and 4294967294) are displaying the same (i.e. wrong) even in TC 6.55.