SmartGWT vs3.0

I am stuck in a problem .
I am unable to get DataSource value on Client code.

[WARN] 404 - GET /smartgwt/sc/DataSourceLoader?dataSource=login (127.0.0.1) 1414 bytes
Request headers
Host: 127.0.0.1:8888
User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:23.0) Gecko/20100101 Firefox/23.0
Accept: */*
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Connection: keep-alive
Referer: http://127.0.0.1:8888/SmartGWT.html?gwt.codesvr=127.0.0.1:9997
Response headers
Content-Type: text/html; charset=iso-8859-1
Content-Length: 1414
[WARN] 404 - GET /smartgwt/sc/DataSourceLoader?dataSource=login (127.0.0.1) 1414 bytes
Request headers
Host: 127.0.0.1:8888
User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:23.0) Gecko/20100101 Firefox/23.0
Accept: */*
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Connection: keep-alive
Referer: http://127.0.0.1:8888/SmartGWT.html?gwt.codesvr=127.0.0.1:9997
Response headers
Content-Type: text/html; charset=iso-8859-1
Content-Length: 1414
Data Source null



I am printing datasource value i am getting on performing DataSource.get("login").
I made login.ds.xml