Just head over to - http://www.numberingplans.com/?page=analysis&sub=imeinr and put the IMEI number of your handset in the blank box and click on analyse button. Now it will give you complete information of your handset.
Here is my experiment -
When I put EMEI number of of my nokia c3, it showed all the information correctly. But when I enter IMEI number of a china mobile, it came up with this message, "This IMEI number seems to be correct, but we do not have any information on this specific handset. Please add the missing information below."
Alternatively you can send IMEI number of the mobile to 53232, either you will get a reply of valid imei or invalid imei.
Hope this helps.