HotSpot 1.3-fcsN (sparc) displays suspicious version info,
so that its version looks like 2.0 instead of 1.3:

    >>>> java -version
    java version "1.3.0"
    Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.0-M)
    Java HotSpot(TM) Core VM (build 2.0, interpreted mode)

Note, that HS 1.3-fcsM clearly reports its version as Client VM 1.3:

    >>>> java -version
    java version "1.3.0"
    Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.0-M)
    Java HotSpot (TM) Client VM (build 1.3-M, interpreted mode)

I've got the HS 1.3-fcsN from the directory:
    /net/mizu/usr/re/hotsparc_client1.3/binaries/solsparc/n-99-10-29
and installed it over JDK 1.3.0M

Machine used to obtain this version report is:
    Ultra-5, 128Mb RAM, Solaris 2.7