I believe that in your distribution you should provide the condensed fonts also as fonts having distinct names (i.e. "DejaVu Sans Cond" & "DejaVu Serif Cond", having the standard styles: Regular, Oblique, Bold, Bold Oblique), not only as styles of the existing fonts. I have no idea what applications happen to be used by the developers of these fonts, but even if these fonts have already existed for several years, I have never been able to use them even for one second. At least on Linux, where I have attempted to use them, I have never encountered any useful application that would allow me to select successfully one of the condensed fonts, i.e. no popular application, e.g. OpenOffice, Firefox, Opera, Konqueror, etc. can use them. This feature requires almost zero effort to implement, but would be helpful for many people, because I have seen many other messages in various forums complaining about the same thing. In an ideal world, all the other applications should be rewritten, but this will never happen. Since there exists a very simple solution for this problem, it should be implemented.
This is a long story, and the short explanation is that we provide two methods in the font: one where the condensed faces belong the the bigger Sans/Serif family, and one where the condensed faces have distinct names (as you request). We basically let the programs decide which one they want. However, in most Linux programs selecting fonts will all go through fontconfig. Fontconfig supports different styles so it selects the first option. It however ignores the fact that most programs making use of fontconfig don't support styles other than bold and/or italic (or don't support it the way they should), and that makes some styles unavailable. So, the "culprit" here is fontconfig, which should in an ideal world ask the program if it can handle more styles and if not, feed it the distinct names. "Fixing" the font by removing the better method would be the world on its head, you can't get every font foundry in the world to change their fonts. So we won't do that either.
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