It's named after the capital city of Central Java in Indonesia, Semarang. It was created by Chinese immigrants in the city of Semarang. It is filled with bamboo shoots, dried shrimp (ebi in Indonesian) chicken and/or prawn. It is served with lumpia sauce that is made from dried shrimp (optional), coconut sugar, red chillies, bird's eye chilies, water, ground white pepper, tapioca starch and water and can be served in either fried or unfried condition.


source : http://en.wikipedia.org/wiki/Lumpia#Lumpia_Semarang
pic taken from : http://www.sedap-sekejap.com/artikel/2001/edisi8/images/lsemarang.jpg