well, the "Anti-spam filters triggered" message seems to be very sensitive and is triggered by almost anything i test post - so i decided to empty/blank spam.txt and use captcha enabled instead.
the only problem im having is that wakaba oekaki doesnt/cant/wont use the codes generated by captcha. it only applies to oekaki, normal posts/uploads work fine.
soo.. if i disable captcha AND spam.txt i have no form of protection :)