SENDING MMS TO POLAND

Can anyone help. I am having problems sending and receiving MMS to and from my friend in Poland. She uses the Plus GSM network. I can receive MMS when I am in Poland from my friends in the UK. All get from her is a message to log on to the internet to veiw the MMS. My Polish friend can send and receive MMS from people in Poland. Is this a general problem Plus GSM in that internationally sent MMS cannot be sent to someones phone ?

for sure its not problem generally, my family use too Plus GSM and withut any problems they sending sms and mms to people aut Poland and aut Europ.
It must be some personal problem.. :(