Cactus was a recruitment agency up until 2008. The minimum requirement to teach English in Portugal is a BA and a 100-hour TESOL/TEFL course (online or on-site). You can also take an advanced program like Trinity, CELTA, or TESL Canada. Ontesol offers a standard 100-hour online course as well as an advanced 250-hour course with practicum that is recognized by TESL Canada Professional Standard 2. The later is an extended version of Coventry House International's 5-week Trinity CertTESOL program (Recognized by TESL Canada Professional Standard 1).
Also consider that you need a EU passport to teach in Europe.

Happy holidays!!
Lucas from Ontesol
www.ontesol.com