Hello Sylvain, I finally found the time to play with the RRLP encoding of the GPS assistance data, sorry for the long delay. When comparing the encoded PDUs with the data from an evaluation version of a commercial ASN1 too, I found several problems which seem to come from a bug in the ASN1 unaligned PER encoder of ASN1C. I can also confirm this problem by simply trying to decode the generated PDUs with the ASN1 decoder from ASN1C, it shows the same error as the commercial tool. I think I have found the bug and a fix for it, however I have not yet confirmed that it really works with a phone, I currently just check the PDUs. I will try to test it with a phone, if anyone is currently playing with RRLP, I can of course send the bug fix (I am just not yet 100% sure with it). Just in case, I use ASN1C from the SourceForge subversion repository. Best regards, Dieter -- Dieter Spaar, Germany spaar(a)mirider.augusta.de