Thank you, mr. i!

In my case this technique involved making the AUTOLOAD routine tag the array routine names (to which tie calls go) with "_nowrap", and modifying the XS linkage routines like this:

SV *
abc_array_fetch (array, index)
    abc_array *array
    IV index
    ALIAS:
        abca_array_fetch=1
        abc_array_fetch_nowrap=2
        abca_array_fetch_nowrap=3
    CODE:
        if (index < 0 && !(ix & 2)) index += array->entries;    
        RETVAL = abc_array_fetch (array, index, ix&1);
[download]

The best part is, it seems to work.

Thanks again,
cmac
www.animalhead.com