Trace id list or (gpx id) retrieved from a bounding box

I'd like the same thing than what's here (more a less) : http://wiki.openstreetmap.org/wiki/API_v0.6#GPS_Traces

1/ but in XAPI I don't want to log in just for retrieving gps traces.

2/ and I just need the IDs Here what I have from your exemple with api v0.6
<trk>
<name>20110625.gpx</name>
<desc> support ride</desc>
<url>api.openstreetmap.org/trace/1040543/view</url>

<trkpt lat="51.631283" lon="3.3e-05">
<time>2011-06-25T08:57:54Z</time>
</trkpt>

<trkpt lat="51.631257" lon="9.6e-05">
<time>2011-06-25T08:57:55Z</time>
</trkpt>

...
...
</trk>

here is what I wish (more or less) ... I fact I don't need to overload your server with long resquest when I just need the ID.
<trk>
<name>20110625.gpx</name>
<desc> support ride</desc>
<url>api.openstreetmap.org/trace/1040543/view</url>
</trk>

or even better
<trk>
<name>20110625.gpx</name>
<desc> support ride</desc>
<url>api.openstreetmap.org/trace/1040543/view</url>
<id>1040543</id>
</trk>

Why ? because I am developing a small tool for android named "Osm Mapper Helper", and I'd like to spot roads, streets already having good traces (not too old, with small point interval ). I'd like to filter traces younger than 12months, 18months, 24months.... why ? (again) because where I live (for the moment) every thing's changing quickly. Most of the atlas you buy are wrong !!! With an Id list, I can easily detect what's already available and what's new a bounding box.