fedora core 8 i386

i want to make sure my mail server is behaving as expected. the past two nights, i've received logwatch notices below. the section in question is the 20 or so deferrals from some .ru e-mail address. i've since removed the user that registered on my wordpress blog (wlvp@yandex.ru) and added the three IP address to iptables DROP, but these "e-mails" still look like they're in some queue unless i'm reading wrong. i've removed known usernames in case you find the numbers useful. why are all these deferred messages here? if they're stuck in a queue, can i remove them? the section in bold below in my concern. thanks in advance!

--------------------- Postfix Begin ------------------------

****** Summary *************************************************************************************

100.784K Bytes accepted 103,203
100.232K Bytes delivered 102,638
======== ================================================

174 Accepted 100.00%
-------- ------------------------------------------------
174 Total 100.00%
======== ================================================

173 Removed from queue
171 Delivered
2 Sent via SMTP
1 Deferred
20 Deferrals



****** Detailed ************************************************************************************

171 Delivered -------------------------------------------------------------------------------
168 ***.net
168 ***
168 ***@***
3 ***.net
3 ***
1 ***

2 Sent via SMTP ---------------------------------------------------------------------------
1 ***.tv
1 ***
1 ***.com
1 ***

20 Deferrals -------------------------------------------------------------------------------
20 4.5.1: Persistent Transient Failure: Mail Delivery Protocol Status:
Invalid command...
20 The recipient has exceeded their message rate limit. Try again
later.: in reply ...
20 yandex.ru
20 wlvp
8 93.158.134.89 mx.yandex.ru
6 77.88.21.89 mx.yandex.ru
6 213.180.204.89 mx.yandex.ru


---------------------- Postfix End -------------------------

this worked. thank you