diff --git a/code/ryzom/client/src/client.cpp b/code/ryzom/client/src/client.cpp
index c92bb887b..4c0121d2e 100644
--- a/code/ryzom/client/src/client.cpp
+++ b/code/ryzom/client/src/client.cpp
@@ -205,6 +205,19 @@ int main(int argc, char **argv)
 		{
 			LoginPassword = Args.getAdditionalArg("password").front();
 
+			// password in hexadecimal
+			if (LoginPassword.compare(0, 2, "0x") == 0)
+			{
+				std::string decodedPassword;
+
+				// decode password
+				if (fromHexa(LoginPassword.substr(2), decodedPassword))
+				{
+					// only use it if real hexadecimal
+					LoginPassword = decodedPassword;
+				}
+			}
+
 			if (Args.haveAdditionalArg("shard_id"))
 				sLoginShardId = Args.getAdditionalArg("shard_id").front();
 		}
diff --git a/code/ryzom/client/src/login_patch.cpp b/code/ryzom/client/src/login_patch.cpp
index f13d1a782..27ade135e 100644
--- a/code/ryzom/client/src/login_patch.cpp
+++ b/code/ryzom/client/src/login_patch.cpp
@@ -1036,7 +1036,8 @@ void CPatchManager::executeBatchFile()
 	
 		if (!LoginPassword.empty())
 		{
-			arguments.push_back(LoginPassword);
+			// encode password in hexadecimal to avoid invalid characters on command-line
+			arguments.push_back("0x" + toHexa(LoginPassword));
 
 			if (!r2Mode)
 			{