Hi Friends,
This is logs of my mail log:
mail for yahoo.com.tw is using up 4001 of 6992 active queue entries : 1 Time(s)
mail for yahoo.com.tw is using up 4001 of 7018 active queue entries : 1 Time(s)
mail for yahoo.com.tw is using up 4001 of 7072 active queue entries : 1 Time(s)
please avoid flushing the whole queue when you have : 75 Time(s)
so that Postfix quickly skips unavailable hosts : 7 Time(s)
so that Postfix wastes less time on undeliverable mail : 7 Time(s)
this may slow down other mail deliveries : 21 Time(s)
to turn off these warnings specify: qmgr_clog_warn_time = 0 : 75 Time(s)
you may need a separate master.cf transport for yahoo.com.tw : 67 Time(s)
you may need to increase the main.cf minimal_backoff_time and maximal_backoff_time : 7 Time(s)
you may need to increase the main.cf spamfilter_destination_concurrency_limit from 20 : 1 Time(s)
you may need to increase the master.cf spamfilter process limit : 7 Time(s)
you may need to reduce spamfilter connect and helo timeouts : 7 Time(s)
My mails queues are filled with some unknown mails :
qshape
T 5 10 20 40 80 160 320 640 1280 1280+
TOTAL 33678 0 0 0 0 0 0 0 0 0 33678
yahoo.com.tw 33501 0 0 0 0 0 0 0 0 0 33501
kimo.com 170 0 0 0 0 0 0 0 0 0 170
ymail.com 3 0 0 0 0 0 0 0 0 0 3
yahoo.com.hk 2 0 0 0 0 0 0 0 0 0 2
rocketmail.com 1 0 0 0 0 0 0 0 0 0 1
allthebestintentions.com 1 0 0 0 0 0 0 0 0 0 1
Its generating huge delay in my mail box 
seems dead
Please instruct me for solution 
How can i add spam filters/configure some security features in postfix configuration..
Thanks All 