diff --git a/extensions/libxt_ipp2p.c b/extensions/libxt_ipp2p.c
index f2c7c45..fb6d2fa 100644
--- a/extensions/libxt_ipp2p.c
+++ b/extensions/libxt_ipp2p.c
@@ -6,6 +6,7 @@
 #include <ctype.h>
 #include <xtables.h>
 #include "xt_ipp2p.h"
+#define param_act(t, s, f) param_act((t), "ipp2p", (s), (f))
 
 static void ipp2p_mt_help(void)
 {
@@ -60,138 +61,104 @@ static int ipp2p_mt_parse(int c, char **argv, int invert, unsigned int *flags,
 
 	switch (c) {
 	case '2':		/*cmd: edk*/
-		if ((*flags & IPP2P_EDK) == IPP2P_EDK)
+		param_act(P_ONLY_ONCE, "--edk", *flags & IPP2P_EDK);
+		param_act(P_NO_INVERT, "--edk", invert);
+		if (*flags & IPP2P_DATA_EDK)
 			exit_error(PARAMETER_PROBLEM,
-				"ipp2p: `--edk' may only be "
-				"specified once");
-		if ((*flags & IPP2P_DATA_EDK) == IPP2P_DATA_EDK)
-		exit_error(PARAMETER_PROBLEM,
 				"ipp2p: use `--edk' OR `--edk-data' but not both of them!");
-		if (invert) exit_error(PARAMETER_PROBLEM, "ipp2p: invert [!] is not allowed!");
 		*flags    |= IPP2P_EDK;
 		info->cmd |= IPP2P_EDK;
 		break;
 
 	case '7':		/*cmd: dc*/
-		if ((*flags & IPP2P_DC) == IPP2P_DC)
-		exit_error(PARAMETER_PROBLEM,
-				"ipp2p: `--dc' may only be "
-				"specified once!");
-		if ((*flags & IPP2P_DATA_DC) == IPP2P_DATA_DC)
-		exit_error(PARAMETER_PROBLEM,
+		param_act(P_ONLY_ONCE, "--dc", *flags & IPP2P_DC);
+		param_act(P_NO_INVERT, "--dc", invert);
+		if (*flags & IPP2P_DATA_DC)
+			exit_error(PARAMETER_PROBLEM,
 				"ipp2p: use `--dc' OR `--dc-data' but not both of them!");
-		if (invert) exit_error(PARAMETER_PROBLEM, "ipp2p: invert [!] is not allowed!");
 		*flags    |= IPP2P_DC;
 		info->cmd |= IPP2P_DC;
 		break;
 
 	case '9':		/*cmd: gnu*/
-		if ((*flags & IPP2P_GNU) == IPP2P_GNU)
-		exit_error(PARAMETER_PROBLEM,
-				"ipp2p: `--gnu' may only be "
-				"specified once!");
-		if ((*flags & IPP2P_DATA_GNU) == IPP2P_DATA_GNU)
-		exit_error(PARAMETER_PROBLEM,
+		param_act(P_ONLY_ONCE, "--gnu", *flags & IPP2P_GNU);
+		param_act(P_NO_INVERT, "--gnu", invert);
+		if (*flags & IPP2P_DATA_GNU)
+			exit_error(PARAMETER_PROBLEM,
 				"ipp2p: use `--gnu' OR `--gnu-data' but not both of them!");
-		if (invert) exit_error(PARAMETER_PROBLEM, "ipp2p: invert [!] is not allowed!");
 		*flags    |= IPP2P_GNU;
 		info->cmd |= IPP2P_GNU;
 		break;
 
 	case 'a':		/*cmd: kazaa*/
-		if ((*flags & IPP2P_KAZAA) == IPP2P_KAZAA)
-		exit_error(PARAMETER_PROBLEM,
-				"ipp2p: `--kazaa' may only be "
-				"specified once!");
-		if ((*flags & IPP2P_DATA_KAZAA) == IPP2P_DATA_KAZAA)
-		exit_error(PARAMETER_PROBLEM,
+		param_act(P_ONLY_ONCE, "--kazaa", *flags & IPP2P_KAZAA);
+		param_act(P_NO_INVERT, "--kazaa", invert);
+		if (*flags & IPP2P_DATA_KAZAA)
+			exit_error(PARAMETER_PROBLEM,
 				"ipp2p: use `--kazaa' OR `--kazaa-data' but not both of them!");
-		if (invert) exit_error(PARAMETER_PROBLEM, "ipp2p: invert [!] is not allowed!");
 		*flags    |= IPP2P_KAZAA;
 		info->cmd |= IPP2P_KAZAA;
 		break;
 
 	case 'b':		/*cmd: bit*/
-		if ((*flags & IPP2P_BIT) == IPP2P_BIT)
-		exit_error(PARAMETER_PROBLEM,
-				"ipp2p: `--bit' may only be "
-				"specified once!");
+		param_act(P_ONLY_ONCE, "--kazaa", *flags & IPP2P_BIT);
+		param_act(P_NO_INVERT, "--kazaa", invert);
 		*flags    |= IPP2P_BIT;
 		info->cmd |= IPP2P_BIT;
 		break;
 
 	case 'c':		/*cmd: apple*/
-		if ((*flags & IPP2P_APPLE) == IPP2P_APPLE)
-		exit_error(PARAMETER_PROBLEM,
-				"ipp2p: `--apple' may only be "
-				"specified once!");
-		if (invert) exit_error(PARAMETER_PROBLEM, "ipp2p: invert [!] is not allowed!");
+		param_act(P_ONLY_ONCE, "--apple", *flags & IPP2P_APPLE);
+		param_act(P_NO_INVERT, "--apple", invert);
 		*flags    |= IPP2P_APPLE;
 		info->cmd |= IPP2P_APPLE;
 		break;
 
 	case 'd':		/*cmd: soul*/
-		if ((*flags & IPP2P_SOUL) == IPP2P_SOUL)
-		exit_error(PARAMETER_PROBLEM,
-				"ipp2p: `--soul' may only be "
-				"specified once!");
-		if (invert) exit_error(PARAMETER_PROBLEM, "ipp2p: invert [!] is not allowed!");
+		param_act(P_ONLY_ONCE, "--soul", *flags & IPP2P_SOUL);
+		param_act(P_NO_INVERT, "--soul", invert);
 		*flags    |= IPP2P_SOUL;
 		info->cmd |= IPP2P_SOUL;
 		break;
 
 	case 'e':		/*cmd: winmx*/
-		if ((*flags & IPP2P_WINMX) == IPP2P_WINMX)
-		exit_error(PARAMETER_PROBLEM,
-				"ipp2p: `--winmx' may only be "
-				"specified once!");
-		if (invert) exit_error(PARAMETER_PROBLEM, "ipp2p: invert [!] is not allowed!");
+		param_act(P_ONLY_ONCE, "--winmx", *flags & IPP2P_WINMX);
+		param_act(P_NO_INVERT, "--winmx", invert);
 		*flags    |= IPP2P_WINMX;
 		info->cmd |= IPP2P_WINMX;
 		break;
 
 	case 'f':		/*cmd: ares*/
-		if ((*flags & IPP2P_ARES) == IPP2P_ARES)
-		exit_error(PARAMETER_PROBLEM,
-				"ipp2p: `--ares' may only be "
-				"specified once!");
-		if (invert) exit_error(PARAMETER_PROBLEM, "ipp2p: invert [!] is not allowed!");
+		param_act(P_ONLY_ONCE, "--ares", *flags & IPP2P_ARES);
+		param_act(P_NO_INVERT, "--ares", invert);
 		*flags    |= IPP2P_ARES;
 		info->cmd |= IPP2P_ARES;
 		break;
 
 	case 'g':		/*cmd: mute*/
-		if ((*flags & IPP2P_MUTE) == IPP2P_MUTE)
-		exit_error(PARAMETER_PROBLEM,
-				"ipp2p: `--mute' may only be "
-				"specified once!");
-		if (invert) exit_error(PARAMETER_PROBLEM, "ipp2p: invert [!] is not allowed!");
+		param_act(P_ONLY_ONCE, "--mute", *flags & IPP2P_MUTE);
+		param_act(P_NO_INVERT, "--mute", invert);
 		*flags    |= IPP2P_MUTE;
 		info->cmd |= IPP2P_MUTE;
 		break;
 
 	case 'h':		/*cmd: waste*/
-		if ((*flags & IPP2P_WASTE) == IPP2P_WASTE)
-		exit_error(PARAMETER_PROBLEM,
-				"ipp2p: `--waste' may only be "
-				"specified once!");
-		if (invert) exit_error(PARAMETER_PROBLEM, "ipp2p: invert [!] is not allowed!");
+		param_act(P_ONLY_ONCE, "--waste", *flags & IPP2P_WASTE);
+		param_act(P_NO_INVERT, "--waste", invert);
 		*flags    |= IPP2P_WASTE;
 		info->cmd |= IPP2P_WASTE;
 		break;
 
 	case 'i':		/*cmd: xdcc*/
-		if ((*flags & IPP2P_XDCC) == IPP2P_XDCC)
-		exit_error(PARAMETER_PROBLEM,
-				"ipp2p: `--ares' may only be "
-				"specified once!");
-		if (invert) exit_error(PARAMETER_PROBLEM, "ipp2p: invert [!] is not allowed!");
+		param_act(P_ONLY_ONCE, "--xdcc", *flags & IPP2P_XDCC);
+		param_act(P_NO_INVERT, "--xdcc", invert);
 		*flags    |= IPP2P_XDCC;
 		info->cmd |= IPP2P_XDCC;
 		break;
 
 	case 'j':		/*cmd: debug*/
-		if (invert) exit_error(PARAMETER_PROBLEM, "ipp2p: invert [!] is not allowed!");
+		param_act(P_ONLY_ONCE, "--debug", info->debug);
+		param_act(P_NO_INVERT, "--debug", invert);
 		info->debug = 1;
 		break;