Is she still holding a Philippine passport or is she an Austrian citizen now? If she's still a Filipino citizen, she has to renew/change her passport if she wants to use her married name. I'm not sure if there are special requirements for someone living in Austria. You can contact the Philippine Embassy in Austria for more details.
ADDRESS: Philippine Embassy in Vienna, Austria
Laurenzerberg 2/2/ZWG
1010 Vienna
AustriaTELEPHONE: (+43) 1 533 2401
(+43) 1 533 2401FAX: (+43) 1 533 2401
(+43) 1 533-2424EMAIL: vienna.pe@dfa.gov.ph
office@philippine-embassy.atWEBSITE: www.philippine-embassy.at FACEBOOK PAGE: https://www.facebook.com/pages/Philippine-Embassy-and-Permanent-Mission-Vienna/205789479431374 HEAD OF MISSION: Ms Lourdes O. Yarraguierre, Ambassador