Strange bug in color property inspector, linux only

[Basile B.]

Setup:
- Lazarus 1.4 RC2 but was already here before
- Linux opensuse 13.2 64 bit

Description:

After a color is edited in a TIGrid, an error is shown, saying that "" is not a valid integer.
The issue cannot be reproduced in a simple sample. In a simple sample this works perfectly (e.g set a TIGrid object on the current form and edit the font color.)

The bug only happens if i use the color mixer to select, not with the clXXX constants.
In a first time, the combobox which should display the hex value is empty then i get the message matching to the first screenshot. After the error message, the color value is properly displayed.

In debug mode, the error seems to appends in a convertion routine (StrToInt64), as shown in the second screenshot.

Any idea of the origin of the bug ?