[josm-dev] Imagery problem with zoom 19

[Willi]

The bilingual Thai-English map "osm-then" provides tiles up to zoom level
19, e.g.
http://thaimap.osm-tools.org/?zoom=19&lat=16.43018&lon=102.8318&layers=B00.
But when I increase the zoom level in JOSM Imagery I get the console message

"current zoom lvl (18) couldnt be increased. MaxZoomLvl (18) reached." 

I've appended more details. Am I doing something wrong or is this a bug? 

Willi


*************************************************
I did the following:
Start JOSM.
Add name "osm-then" and URL "tms:http://tile.osm-tools.org/osm_then" in
settings / WMSTMS.
Download
"http://www.openstreetmap.org/?lat=16.4295&lon=102.8318&zoom=18&layers=M".
Select Imagery / osm-then.
Right-click on the image. Click Increase zoom.
Messages on console:
  GET
http://api.openstreetmap.org/api/0.6/map?bbox=102.83111339999999,16.4291567,
102.8324866,16.429843299999998
  clicked on tile: 205951 118940 currentZoomLevel: 18
  current zoom lvl (18) couldnt be increased. MaxZoomLvl (18) reached.

JOSM status report says:

Repository Root: http://josm.openstreetmap.de/svn
Build-Date: 2011-01-21 07:37:34
Last Changed Author: framm
Revision: 3793
Repository UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
URL: http://josm.openstreetmap.de/svn/trunk
Last Changed Date: 2011-01-21 08:35:14 +0100 (Fri, 21 Jan 2011)
Last Changed Rev: 3793

Identification: JOSM/1.5 (3793 de)
Memory Usage: 222 MB / 989 MB (40 MB allocated, but free)
Java version: 1.6.0_23, Sun Microsystems Inc., Java HotSpot(TM) Client VM
Operating system: Windows 7
Dataset consistency test: No problems found

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