Register allocation bug in IMCC? Or misunderstanding on my part?

[Clinton A. Pierce]

The following code:

.local PerlArray READDATA
.local PerlHash  RESTOREINFO
.sub _main
        READDATA = new PerlArray
        RESTOREINFO = new PerlHash
        call _data
        end
.end
.sub _data
        push READDATA, 10
        ret
.end
Throws an error in the VM of:

        push_integer() not implemented in class 'PerlHash'

This is, as far as I can tell, because the same register is used by IMCC 
for both the READDATA and RESTOREINFO locals, thus by the time that the sub 
_data gets around to being run, READDATA has become a PerlHash (imcc -t):

PC=0; OP=821 (new_p_ic); ARGS=(P0, 14)
PC=3; OP=821 (new_p_ic); ARGS=(P0, 15)
PC=6; OP=752 (bsr_ic); ARGS=(2)
PC=8; OP=722 (push_p_ic); ARGS=(P0, 10)
push_integer() not implemented in class 'PerlHash'
This seems to conflict with the example that Leo gave me on the 28th.  I'm 
not sure if this is a bug or if I've got some whacky misunderstanding of 
how things work.  I think my intention is clear by the above piece of 
code.  Suggestions?

As a postscript, changing the code to:

.local PerlArray READDATA
.local PerlHash  RESTOREINFO
.sub _main
        READDATA = new PerlArray
        RESTOREINFO = new PerlHash
        push READDATA, 10
        end
.end
Produces the desired (and expected) output.  READDATA and RESTOREINFO each 
get their own register:

PC=0; OP=821 (new_p_ic); ARGS=(P0, 14)
PC=3; OP=821 (new_p_ic); ARGS=(P1, 15)
PC=6; OP=722 (push_p_ic); ARGS=(P0, 10)
PC=9; OP=0 (end)
This was all done with imcc, cvs updated as of 12:00 Eastern time.  No 
optimization options selected.