That's the right idea, but actually it's a contraction of the German words for double cab:
"doppel" and "kabine", written as one word, doppelkabine.  Hence the "k" in doka.
You say the "e" on the end like the e in "etka", so kabine is three syllables.
Here's a German web site about them:
http://www.doppelkabine.de/

-Hans

----- Original Message -----
From: "Christopher Gronski" <gronski@GMAIL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, November 02, 2005 8:02 AM
Subject: Re: Dokas, Dokas, Dokas!!

Doka = DOuble KAb (ie: Double Cab)

On 11/2/05, Doug Alcock <doug.alcock@gmail.com> wrote:
> Uhhh --- so what's a Doka??
>  Cheers,
> Doug
>
>  On 11/2/05, JordanVw@aol.com <JordanVw@aol.com> wrote:
> >
> > wow, this fall is a bumper crop for dokas! heres some more..
> > not mine..
> >
> > http://www.thesamba.com/vw/classifieds/detail.php?id=210678
> >
> > and another one...
> >
> > http://www.thesamba.com/vw/classifieds/detail.php?id=77252
> >
>