On Lubuntu, even manual xorg.conf creation can't help to set this mode.
1) Driver creates the list of available modes, ignoring xorg.conf. Maximum resolution is 800x600 because testing 1024x768x24 causes obvoius fail.
2) Driver reads the "1024x768x16" line and sets "800x600x16" because 800x600 is "maximum".
The following quick hack http://www.lubuntu.ru/forum/viewtopic.php?f=12&t=523&p=9941#p9907 allows to use this mode. Of course, this rough solution can't be recommended.
Guys, opensource goes downhill with such "architectures".
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