diff --git a/eth/main.cpp b/eth/main.cpp
index ba12ff8ef..7b2767757 100644
--- a/eth/main.cpp
+++ b/eth/main.cpp
@@ -418,7 +418,8 @@ int main(int argc, char** argv)
 				auto h = bc.currentHash();
 				auto blockData = bc.block(h);
 				BlockInfo info(blockData);
-				if(iss.peek()!=-1){
+				if (iss.peek() != -1)
+				{
 					string hexAddr;
 					u256 amount;
 					u256 gasPrice;
@@ -445,8 +446,6 @@ int main(int argc, char** argv)
 						if (size > 0)
 							cwarn << "Invalid address length: " << size;
 					}
-					else if (amount < 0)
-						cwarn << "Invalid amount: " << amount;
 					else if (gasPrice < info.minGasPrice)
 						cwarn << "Minimum gas price is " << info.minGasPrice;
 					else if (gas < minGas)
@@ -462,9 +461,9 @@ int main(int argc, char** argv)
 						Address dest = h160(fromHex(hexAddr));
 						c.transact(secret, amount, dest, data, gas, gasPrice);
 					}
-				} else {
-					cwarn << "Require parameters: transact ADDRESS AMOUNT GASPRICE GAS SECRET DATA";
 				}
+				else
+					cwarn << "Require parameters: transact ADDRESS AMOUNT GASPRICE GAS SECRET DATA";
 			}
 			else if (cmd == "listContracts")
 			{
@@ -502,7 +501,8 @@ int main(int argc, char** argv)
 			else if (cmd == "send")
 			{
 				ClientGuard g(&c);
-				if(iss.peek() != -1){
+				if (iss.peek() != -1)
+				{
 					string hexAddr;
 					u256 amount;
 					int size = hexAddr.length();
@@ -513,9 +513,8 @@ int main(int argc, char** argv)
 						if (size > 0)
 							cwarn << "Invalid address length: " << size;
 					}
-					else if (amount < 0) {
-						cwarn << "Invalid amount: " << amount;
-					} else {
+					else 
+					{
 						auto const& bc = c.blockChain();
 						auto h = bc.currentHash();
 						auto blockData = bc.block(h);
@@ -525,9 +524,9 @@ int main(int argc, char** argv)
 						c.transact(us.secret(), amount, dest, bytes(), minGas, info.minGasPrice);
 					}
 					
-				} else {
+				} 
+				else
 					cwarn << "Require parameters: send ADDRESS AMOUNT";
-				}
 			}
 			else if (cmd == "contract")
 			{
@@ -568,12 +567,10 @@ int main(int argc, char** argv)
 					else if (gas < minGas)
 						cwarn << "Minimum gas amount is " << minGas;
 					else
-					{
 						c.transact(us.secret(), endowment, init, gas, gasPrice);
-					}
-				} else {
+				} 
+				else
 					cwarn << "Require parameters: contract ENDOWMENT GASPRICE GAS CODEHEX";
-				}
 			}
 			else if (cmd == "inspect")
 			{
@@ -602,9 +599,60 @@ int main(int argc, char** argv)
 			}
 			else if (cmd == "setSecret")
 			{
-				string hexSec;
-				iss >> hexSec;
-				us = KeyPair(h256(fromHex(hexSec)));
+				if (iss.peek() != -1)
+				{
+					string hexSec;
+					iss >> hexSec;
+					us = KeyPair(h256(fromHex(hexSec)));
+				} 
+				else
+					cwarn << "Require parameter: setSecret HEXSECRETKEY";
+			}
+			else if (cmd == "setAddress")
+			{
+				if (iss.peek() != -1)
+				{
+					string hexAddr;
+					iss >> hexAddr;
+					if (hexAddr.length() != 40)
+						cwarn << "Invalid address length: " << hexAddr.length();
+					else
+						coinbase = h160(fromHex(hexAddr));
+				} 
+				else
+					cwarn << "Require parameter: setAddress HEXADDRESS";
+			}
+			else if (cmd == "exportConfig")
+			{
+				if (iss.peek() != -1)
+				{
+					string path;
+					iss >> path;
+					RLPStream config(2);
+					config << us.secret() << coinbase;
+					writeFile(path, config.out());
+				} 
+				else
+					cwarn << "Require parameter: exportConfig PATH";
+			}
+			else if (cmd == "importConfig")
+			{
+				if (iss.peek() != -1)
+				{
+					string path;
+					iss >> path;
+					bytes b = contents(path);
+					if (b.size())
+					{
+						RLP config(b);
+						us = KeyPair(config[0].toHash<Secret>());
+						coinbase = config[1].toHash<Address>();
+					} 
+					else
+						cwarn << path << "has no content!";
+				} 
+				else
+					cwarn << "Require parameter: importConfig PATH";
 			}
 			else if (cmd == "help")
 				interactiveHelp();
diff --git a/neth/main.cpp b/neth/main.cpp
index a350a9d75..2078da004 100644
--- a/neth/main.cpp
+++ b/neth/main.cpp
@@ -665,8 +665,6 @@ int main(int argc, char** argv)
 					if (size > 0)
 						cwarn << "Invalid address length: " << size;
 				}
-				else if (amount < 0)
-					cwarn << "Invalid amount: " << amount;
 				else if (gasPrice < info.minGasPrice)
 					cwarn << "Minimum gas price is " << info.minGasPrice;
 				else if (gas < minGas)
@@ -712,8 +710,6 @@ int main(int argc, char** argv)
 					if (size > 0)
 						cwarn << "Invalid address length: " << size;
 				}
-				else if (amount <= 0)
-					cwarn << "Invalid amount: " << amount;
 				else
 				{
 					auto const& bc = c.blockChain();