Description:
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Hello. I think it's important to support arbitrary queries in the API. Several projects extends Memcached server functionality, such as memcached-tag. For example, memcached-tag implements two new commands: tag_add and tag_delete. I think the best way to solve the problem is adding command(cmd, arg0, arg1, arg2,...) method returns an answer, and getConnection(server,port) (or getConnection(array) ) method returns pointer of connection to server.
And eventually it would be great to have such functionality (such as memcached-tag) built-in into extension.

memcached-tag - http://code.google.com/p/memcached-tag/

Thank you very much! Good luck.

Reproduce code:
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$memcache->command('tag_add','mytag','myfirstkey');
$memcache->command('tag_add','mytag','mysecondkey');
$memcache->command('tag_delete','mytag');

Expected result:
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Empty :)

Actual result:
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Error :)