Topic: smtp and pop3 Instances

[paradigm]

I'm testing sme server with a large amount of email accounts with pop3 enabled in public mode with authentication

And smtp also enabled in public mode with authentication , i fear that Instances in smtp and pop3 might be reached .

Should i do any thing more then change the Instances value in smtpd like this ?  :

config setprop smtpd Instances xx (more than 40)

Is there an Instances value for pop3  ? (the number of accounts permitted at one point to download mail )

Does smtpd Instances value include all sent mail at one time (inside and outside the network ?)