Address Stored in Local address book changed

When I get a mail, I will normally add the address to my local address book. but when i wanted to send out a mail using this address, this address is changed to my original domain name and not the persons domain name.

Example;

Received e-mail from test.com.my and stored in local address book

then when i want to sent a mail to test.com.my, it chnage the domain name to my original vishnu@perak.com.my

why does this happen and i always get failure delivery message for this change

Please help.

Thank you