[Rdfapi-php-interest] Problem using SparqlClient

Hi All,
I have problem when using sparqlClient method to query dbpedia and cia
factbook datasets. Here are some error message when I used some SPARQL
Endpoint:
1. http://dbpedia.org/sparql :
unable to parse result
server returned:
Error HTTP/1.1 404 File not found
The requested URL was not found    URI  = '/sparql'

2. http://sparlq.org/sparql, there are 2 conditions:
a. if i tried to query dbpedia dataset, there is no result for it.
b. for cia factbook dataset, give this error message:
unable to parse result
server returned:
<followed by expected result>

3. http://lod.openlinksw.com/sparql
a. for dbpedia, it works well
b. for cia factbook, there was no result, except I executed my query
directly in the browser (http://lod.openlinksw.com/sparql) first, then the
expecte result could come.


Can somebody help me to solve this problem? I tried to solve my problem by
changing the sparql endpoint. However, each endpoint lead me to different
problems.

Thank you in advance for your attention.

best regards,
Hendrik