Well this sure is crazy and appears to be undocumented behaviour[1]. But poking at the source for perl 5.6.1 it looks like it's quite normal for perl behave in this way. If you look at the Perl_gv_fetchmethod_autoload function in gv.c you'll find the following lines of code 
gv = gv_fetchmeth(stash, name, nend - name, 0);
if (!gv) {
    if (strEQ(name,"import") || strEQ(name,"unimport"))
        gv = (GV*)&PL_sv_yes;
    else if (autoload)
        gv = gv_autoload4(stash, name, nend - name, TRUE);
}

[download]
So from what I gather the import and unimport methods are automatically handled by perl and internally autoloaded as scalar variables. As to why this is and what purpose it serves I am in totally in the dark.
HTH

_________
broquaint

[1] I sit corrected as Ovid points out in his node that this behaviour is documented albeit surreptitiously

In reply to Re: import() magic by broquaint
in thread import() magic by ferrency

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