Bug#538110: Unusable -- DirectFBError [DirectFBSetOption ("quiet", "")]: Not supported!
directvnc is directly using the configuration item "quiet", which version 1.2.0 of libdirectfb doesn't seem to support.
You can either recompile the source, commenting out line 44 in dfb.c ("DFBCHECK(DirectFBSetOption ("quiet", ""));"), or you can edit the binary with a hex editor (as a very quick and dirty workaround):
1. edit the directvnc binary using a hex editor.
2. search for the string "quiet" (no quotes). You should find two matches.
3. one of the two is immediately surrounded by null bytes (that's the constant string passed to the DirectFBSetOption call; the other is the string used for the error message)
4. replace (don't insert!) 'quiet' with 'vt\0\0\0'--that is, replace the letter q with v, the letter u with t, and the rest of the letters with null characters.
5. save, and directvnc should now work normally.
What this does is replace the option set call for "quiet" with the one for "vt"--a supported option that is set by default (so using it is a no-op unless you specifically wanted no-vt in your .directfbrc)
Benefit of recompiling from source is that it's the proper way to do it, and way safer.
Benefit of the binary hack is that it's much quicker and will get overwritten when the next (hopefully fixed) version is released.