QGIS » QGIS Application

when i try to launch the merge command of gdal, it returns this error

Traceback (most recent call last):
File "C:\\OSGeo4W\\bin\\gdal_merge.py", line 36, in
import gdal
File "C:\\OSGeo4W\\apps\\Python27\\lib\\site-packages\\gdal.py", line 2, in
from osgeo.gdal import deprecation_warn
File "C:\\OSGeo4W\\apps\\Python27\\lib\\site-packages\\osgeo\\__init__.py", line 21, in
gdal = swig_import_helper()
File "C:\\OSGeo4W\\apps\\Python27\\lib\\site-packages\\osgeo\\_init__.py", line 17, in swig_import_helper
_mod = imp.load_module('_gdal', fp, pathname, description)
ImportError: DLL load failed: Impossibile trovare la procedura specificata.

error occurs both in qgis 1.8 and master

same error if i launch the commando from osgeo prompt:

C:\\>gdal_merge.bat -of GTiff -o E:/temp/RiesgoGuaya/Danno_10cm.tif E:/temp/Riesg
oGuaya/Danno_A_10cm.tif E:/temp/RiesgoGuaya/Danno_B_10cm.tif E:/temp/RiesgoGuaya
/Danno_C_10cm.tif
C:\\OSGeo4W\\\\apps\\Python27\\lib\\site.py:158: Warning: 'with' will become a reserve
d keyword in Python 2.6
'import site' failed; use -v for traceback
C:\\OSGeo4W\\\\apps\\Python27\\lib\\linecache.py:127: Warning: 'with' will become a re
served keyword in Python 2.6
Traceback (most recent call last):
File "C:\\OSGeo4W\\\\bin\\gdal_merge.py", line 36, in <module>
import gdal
ImportError: No module named gdal