diff --git a/include/sipp.hpp b/include/sipp.hpp
index 9a533cb6..9462a8c5 100644
--- a/include/sipp.hpp
+++ b/include/sipp.hpp
@@ -55,6 +55,7 @@
 #include <string>
 #include <map>
 #include <set>
+#include <unordered_map>
 #include <math.h>
 #ifdef __SUNOS
 #include <stdarg.h>
@@ -296,7 +297,8 @@ MAYBE_EXTERN int                currentRepartitionToDisplay  DEFVAL(1);
 MAYBE_EXTERN unsigned int       base_cseq               DEFVAL(0);
 MAYBE_EXTERN char             * auth_uri                DEFVAL(0);
 MAYBE_EXTERN const char       * call_id_string          DEFVAL("%u-%p@%s");
-MAYBE_EXTERN char             **generic[100];
+typedef std::unordered_map<std::string, std::string> ParamMap;
+MAYBE_EXTERN ParamMap           generic;
 
 MAYBE_EXTERN bool               rtp_echo_state          DEFVAL(true);
 MAYBE_EXTERN bool               callidSlash             DEFVAL(false);
diff --git a/src/message.cpp b/src/message.cpp
index 535d0496..374b81fd 100644
--- a/src/message.cpp
+++ b/src/message.cpp
@@ -349,19 +349,12 @@ SendingMessage::SendingMessage(scenario* msg_scenario, const char* const_src, bo
                 parseAuthenticationKeyword(msg_scenario, newcomp, keyword);
             } else {
                 // scan for the generic parameters - must be last test
-                int i = 0;
-                while (generic[i]) {
-                    char *msg1 = *generic[i];
-                    char *msg2 = *(generic[i] + 1);
-                    if(!strcmp(keyword, msg1)) {
-                        newcomp->type = E_Message_Literal;
-                        newcomp->literal = strdup(msg2);
-                        newcomp->literalLen = strlen(newcomp->literal);
-                        break;
-                    }
-                    ++i;
-                }
-                if (!generic[i]) {
+                auto gen = generic.find(keyword);
+                if (gen != generic.end()) {
+                    newcomp->type = E_Message_Literal;
+                    newcomp->literal = strdup((*gen).second.c_str());
+                    newcomp->literalLen = strlen(newcomp->literal);
+                } else {
                     ERROR("Unsupported keyword '%s' in xml scenario file",
                           keyword);
                 }
diff --git a/src/sipp.cpp b/src/sipp.cpp
index 69c0973a..ea1055a9 100644
--- a/src/sipp.cpp
+++ b/src/sipp.cpp
@@ -1318,7 +1318,6 @@ int main(int argc, char *argv[])
 {
     int                  argi = 0;
     pthread_t pthread2_id = 0, pthread3_id = 0;
-    unsigned int         generic_count = 0;
     bool                 slave_masterSet = false;
     int rtp_errors;
     int echo_errors;
@@ -1326,8 +1325,6 @@ int main(int argc, char *argv[])
     rtp_errors = 0;
     echo_errors = 0;
 
-    generic[0] = NULL;
-
     /* At least one argument is needed */
     if (argc < 2) {
         help();
@@ -1641,11 +1638,7 @@ int main(int argc, char *argv[])
                 REQUIRE_ARG();
                 CHECK_PASS();
 
-                if (generic_count + 1 >= sizeof(generic)/sizeof(generic[0])) {
-                    ERROR("Too many generic parameters %d",generic_count + 1);
-                }
-                generic[generic_count++] = &argv[argi - 1];
-                generic[generic_count] = NULL;
+                generic[argv[argi - 1]] = argv[argi];
                 break;
             case SIPP_OPTION_VAR:
                 REQUIRE_ARG();