Fixed: [  Issue 30  ]  Services should support more than one RPC elements.
https://code.google.com/p/protobuf-dt/issues/detail?id=30

com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/Protobuf.xtext

diff --git a/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/Protobuf.xtext b/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/Protobuf.xtext
index 7e8fbc7..b359efe 100644
--- a/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/Protobuf.xtext
+++ b/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/Protobuf.xtext
@@ -132,11 +132,11 @@
 
 Service:
  'service' name=ID '{'
-   rpc=Rpc
+   rpcs+=Rpc*
  '}';
 
 Rpc: 
-  'rpc' name=ID  '(' argType=MessageReference ')' 'returns' '(' returnType=MessageReference ')' ';'
+  'rpc' name=ID  '(' argType=MessageReference ')' 'returns' '(' returnType=MessageReference ')' (('{' '}') | ';')
 ;
 
 MessageReference: