vzDoc supports the Specman/e and Vera languages. Both languages change over time, so the level of “support” tends to vary. (The most common ongoing changes to vzDoc are to support extra syntax in one language or the other.)
vzDoc runs on SPARC Solaris (built on Solaris 8) and X86 Linux (built on Red Hat Linux 9). Other Unixoid platforms are candidates for straightforward porting.