SOLUTION A for utf-8 encoded shapefiles
Supposed you are working on Windows, look for qgis.bat in bin directory, and open it with a text editor. after the first line, insert
SET SHAPE_ENCODING=UTF-8
and save. Qgis 1.8.0 has some problems with encoding, using your computers default font instead of the one you specify. It is fixed in Qgis Master (1.9.0) by now, which you can install with osgeo4w setup.
SOLUTION B for ISO-8859-7 encoded shapefiles
We had a similar issue lately on the mailing list:
http://lists.osgeo.org/pipermail/qgis-user/2012-November/020021.html
It works on the cited shapefile only with Qgis Master (1.9.0):
In Settings -> Options -> General, there is a checkbox
[ ] Ignore shapefile encoding
Uncheck it.
Then open the shapefile in QGIS with ISO-8859-7.
With this option shapefile encoding is done the same way as in Qgis 1.7.4, that is leaving it to QGIS and not GDAL.
If you want to work on with QGIS Lisboa, save the shapefile as UTF-8 and proceed with Solution A, until the next stable version of QGIS is released.
SOLUTION C
create a file named < filename >.cpg and 1253 as content in the same folder as the shapefile.
convert the shapefile with ogr2ogr:
ogr2ogr -a_srs EPSG:2100 -f GML nomoi_utf.gml nomoi_okxe.shp
ogr2ogr --config SHAPE_ENCODING "UTF-8" -a_srs EPSG:2100 nomoi_utf.shp nomoi_utf.gml
This allows GDAL to encode ISO-8859-7 on reading, and writes UTF-8. Unfortunately, writing to shp in one step does not work the same way. You can use the GML or the utf.shapefile with Solution A.
