Problem with at_askml function in Postgis

["Hall, Samuel L (Sam)" <sam.hall@xxxxxxxxxxxxxxxxxx>]

Using PostgreSQL 9.1.8 on x86_64-unknown-linux-gnu, compiled by gcc (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3, 64-bit

POSTGIS="2.0.1 r9979" GEOS="3.3.3-CAPI-1.7.4" PROJ="Rel. 4.8.0, 6 March 2012" GDAL="GDAL 1.9.2, released 2012/10/08" LIBXML="2.8.0" LIBJSON="UNKNOWN" TOPOLOGY RASTER

 

Postgis seems to be working fine, but when I try this query

SELECT st_askml(path) FROM paths WHERE jobnumber = '20121491';

 

I get this error

ERROR:  function st_askml(geometry) is not unique

LINE 1: select st_askml(path) from paths where jobnumber = '20121491...

               ^

HINT:  Could not choose a best candidate function. You might need to add explicit type casts.

 

If I change the query to

SELECT st_askml(path,15) FROM paths WHERE jobnumber = '20121491';

 

Then it works

 

 

Both st_askml(geometry)  and st_askml(geometry, integer) are unique.

 

Does anybody know the answer to this problem?