don't check TRANSIENT destination

libi2pd_client/SAM.cpp

@@ -367,6 +367,8 @@ namespace client
 			return;
 		}
 
+		if (destination != SAM_VALUE_TRANSIENT)
+		{	
 			//ensure it's a base64 string
 			i2p::data::PrivateKeys keys;
 			if (!keys.FromBase64(destination))
@@ -374,6 +376,7 @@ namespace client
 				SendMessageReply(SAM_SESSION_STATUS_INVALID_KEY, strlen(SAM_SESSION_STATUS_INVALID_KEY), true);
 				return;
 			}
+		}		
 
 		// create destination
 		auto session = m_Owner.CreateSession (id, destination == SAM_VALUE_TRANSIENT ? "" : destination, &params);