int encode_loaded = 0;
SV *m_encode = newSVpvs ("decode"); /* Or "Encode::decode", I'm not sure */
SV *sv_enc   = newSVpvs ("cp1252");

my_foo (char *buffer)
{
    int result;

    if (!encode_loaded) {
        ENTER;
        load_module (PERL_LOADMOD_NOIMPORT, newSVpvs ("Encode"), NULL, NULL, NULL);
        LEAVE;
        encode_loaded = 1;
        }

    PUSHMARK (sp);
    EXTEND (sp, 2);
    PUSHs (sv_enc);
    PUSHs (newSVpv (buffer));
    PUTBACK;
    result = call_sv (m_encode, G_SCALAR | G_METHOD);
    SPAGAIN;
    if (result) {
        SV *encoded = POPs;
        /* Do more */
        }
    PUTBACK;
    }