Question about GSA email spider

Ok my question is simple

basically i want to use third part email provider to send emails

so my question

lets say i have 2000 yahoo emails with password and username
i want to use these emails to send email

and i have 500k email list

now i am already able to send emails with using these yahoo emails
but my problem is i can not use any proxy server for this job

is gsa email spider capable of this ?

i tried trial but there were nothing simply

so let me rephrase

the web proxy server will connect yahoo smtp server to send email
so i can multi threading send emails with using yahoo smtp

@sven