That's why I mentioned that I'm not sure about extradition to other EU countries. Extradition of its own citizens to other non-EU countries is currently not possible.
1173. Extradition of Austrian nationals is not admissible pursuant to Article 12, paragraph 1 of the ARHG. The authorities mentioned that this provision has the rank of a constitutional provision and, as such, requires a 2/3 majority of Parliament to be amended. Nevertheless, as of January 1, 2009, Austria will be in a position to extradite its own nationals to other EU-Member States in accordance with Section 5 EU-JZG.
1174. Where extradition for ML is denied on the sole ground of nationality, the Austrian courts are competent under Article 65, paragraph 1, no. 1 of the StGB (jurisdiction over acts committed by Austrians abroad) and must conduct the proceedings in the same way as for any other criminal offense under national law. The Austrian courts also have explicit jurisdiction over terrorist acts and terrorist financing when the perpetrator is Austrian (Article 64, paragraph 1, nos. 9 and 10 of the StGB).
The law for this is "§ 12 ARHG Verbot der Auslieferung österreichischer Staatsbürger" which is part of the Austrian constitution: http://www.jusline.at/12_Verbot_der_Auslieferung_%C3%B6sterr...
https://books.google.com/books?id=0H5XqvUu3B4C provides an English explanation of that law:
1173. Extradition of Austrian nationals is not admissible pursuant to Article 12, paragraph 1 of the ARHG. The authorities mentioned that this provision has the rank of a constitutional provision and, as such, requires a 2/3 majority of Parliament to be amended. Nevertheless, as of January 1, 2009, Austria will be in a position to extradite its own nationals to other EU-Member States in accordance with Section 5 EU-JZG.
1174. Where extradition for ML is denied on the sole ground of nationality, the Austrian courts are competent under Article 65, paragraph 1, no. 1 of the StGB (jurisdiction over acts committed by Austrians abroad) and must conduct the proceedings in the same way as for any other criminal offense under national law. The Austrian courts also have explicit jurisdiction over terrorist acts and terrorist financing when the perpetrator is Austrian (Article 64, paragraph 1, nos. 9 and 10 of the StGB).