diff --git a/src/arguments.cc b/src/arguments.cc
index 653a1b8..0b2e8eb 100644
--- a/src/arguments.cc
+++ b/src/arguments.cc
@@ -60,12 +60,16 @@ feature proc_args(int argc, char **argv,
                 } else if (str == "-e") {
                         result |= FEATURE_EXTRA_STUFF;
                 } else if (str == "-E") {
+                        if (result & FEATURE_READ_MAP)
+                                return FEATURE_CONFLICT | i;
+
                         result |= FEATURE_EXTRA_LEVELS;
                 } else if (str == "-o") {
                         result |= FEATURE_WALK_OVER;
                 } else if (str == "-m") {
                         if ((result & FEATURE_RAND_MAP) ||
                             (result & FEATURE_REVISIT) ||
+                            (result & FEATURE_EXTRA_LEVELS) ||
                             (result & FEATURE_READ_MAP))
                                 return FEATURE_CONFLICT | i;
 
@@ -197,9 +201,9 @@ const char *ARGS_LIST = "\
 -t         : Enable throw (will turn on -i)\n\
 -R         : Enable revisiting levels. CANNOT BE USED WITH -m.\n\
 -e         : Enable extra potions and races\n\
--E         : Enable extra levels\n\
+-E         : Enable extra levels. CANNOT BE USED WITH -m.\n\
 -o         : Allows characters to go over gold and potions\n\
--m [file]  : Reads map data from file. CANNOT BE USED WITH -r or -R.\n\
+-m [file]  : Reads map data from file. CANNOT BE USED WITH -r or -R or -E.\n\
 -s [seed]  : Sets initial seed to seed\n\
 -I [file]  : Reads commands from file. CANNOT BE USED WITH -n.\n\
 -O [file]  : Outputs to file. CANNOT BE USED WITH -n.\n\