[postgis-users] PostGIS non functional on Ubuntu 14.04

[Luís de Sousa]

Dear all,

I have the following packages installed on Ubuntu 14.04 (all fetched
with apt from the repositories):
. postgresql-9.3
. postgresql-9.3-postgis-2.1
. libgeos-3.4.2

When I try to add the PostGIS extension to a database I get following message:

$  psql pg_testing -c "create extension postgis"
ERROR:  could not load library
"/usr/lib/postgresql/9.3/lib/postgis-2.1.so":
/usr/lib/liblwgeom-2.1.3.so: undefined symbol:
GEOSDelaunayTriangulation

I have posted full package details at GIS.SE:
http://gis.stackexchange.com/questions/108308/postgis-non-functional-on-ubuntu-14-04

Apparently, there is some mismatch between libgeos and postgis. But I
have the exact same versions indicated in the compile guide at the
Wiki:
http://trac.osgeo.org/postgis/wiki/UsersWikiPostGIS21Ubuntu1310src

Any advice on how to get PostGIS running is welcome. Thank you,

Luís