Thanks George for your valuable information.
Is this issue related to trusted sites?
I tried following options, but still see warning poping up.
1) In user computer, added application url (from where printing is invoked) to trusted sites.
2) Modified registry entry as mentioned in this url: http://www.adobe.com/devnet-docs/acrobatetk/tools/AppSec/enhanced.html ( section 4.6.4).
You need to set the following reg keys :
[HKEY_CURRENT_USER\Software\Adobe\Acrobat Reader\10.0\AVAlert\cCheckbox\cAcrobat] "iWarnScriptPrintAll"=dword:00000001
[HKEY_CURRENT_USER\Software\Adobe\Acrobat Reader\10.0\EWH] "bExecutePrint"=dword:00000001
Tested on Acrobat Reader 10.1.10