Crash when editing table columns

I'm trying to copy a couple of columns from a table into another. The "Copy selected columns" and "Paste columns" parts work fine but as soon as I try to edit the comment in the copied fields HeidiSQL crashes.

date/time         : 2011-02-03, 16:35:42, 388ms
computer name     : SOFT14
user name         : ALVARO.GONZALEZ <admin>
registered owner  : *************
operating system  : Windows XP Service Pack 3 build 2600
system language   : Spanish
system up time    : 21 days 7 hours
program up time   : 23 seconds
processors        : 2x Intel(R) Pentium(R) 4 CPU 3.00GHz
physical memory   : 449/991 MB (free/total)
free disk space   : (C:) 5,42 GB (E:) 12,87 GB
display mode      : 1280x1024, 32 bit
process id        : $d0c
allocated memory  : 9,35 MB
executable        : heidisql.exe
exec. date/time   : 2011-02-03 16:27
version           : 6.0.0.3670
compiled with     : Delphi XE
madExcept version : 3.0m beta 1
callstack crc     : $5020145a, $88d69db6, $88d69db6
exception number  : 1
exception class   : EAccessViolation
exception message : Access violation at address 00626BF2 in module 'heidisql.exe'. Read of address 00000000.
main thread ($7ec):
00626bf2 heidisql.exe VirtualTrees        TBaseVirtualTree.DoEdit
004d8b2e heidisql.exe Controls            TControl.WMMouseMove
0062424c heidisql.exe VirtualTrees        TBaseVirtualTree.WMTimer
004d8208 heidisql.exe Controls            TControl.WndProc
004dcacc heidisql.exe Controls            TWinControl.WndProc
0062f504 heidisql.exe VirtualTrees        TBaseVirtualTree.WndProc
004dc16c heidisql.exe Controls            TWinControl.MainWndProc
004a56ec heidisql.exe Classes             StdWndProc
7e398a0b USER32.dll                       DispatchMessageW
0057638f heidisql.exe Forms               TApplication.ProcessMessage
005763d2 heidisql.exe Forms               TApplication.HandleMessage
005766fd heidisql.exe Forms               TApplication.Run
00795752 heidisql.exe heidisql     66 +15 initialization

Side note: the forum software should probably not try to find smilies in code blocks :)

Reported in issue #2291.