stratum_recv_line failed

[pool2mine]

Hello, i am setting up a yiimp based pool for many CPU coins, many algorithms present problems when adjusting the stratum diff, for example for a Pentium processor that can hash at 300 H/S in lyra2z330 algo, when i set diff to 0.004 some workers can't find a share and keep giving me the stratum_rec_line failed, other workers run fine, then if i set diff to 0.003 i get rid of the stratum error but get all invalid shares for low difficulty, i tried to set difficulty to .00035 but yiimp stratum wont take the fourth decimal, so, for a workaround i was wondering if i can connect the miners to .003 diff port but specify the minimum difficulty in the command line (in the client side) to avoid low diff rejected, i googled a lot trying to find the syntax (if it exist) to set min share diff on miner startup. please let me know if this is possible, will solve a lot of problems to many pools. regards