diff --git a/scripts/e3a/frost.lua b/scripts/e3a/frost.lua
index 31bf9fe6f..f60d557fb 100644
--- a/scripts/e3a/frost.lua
+++ b/scripts/e3a/frost.lua
@@ -13,14 +13,14 @@ end
 local function freeze(r, chance)
     for i, rn in ipairs(r.adj) do
         -- each region has a chance to freeze
-        if rn.terrain=="ocean" and (chance>=100 or math.mod(rng_int(), 100)<chance) then
+        if rn.terrain=="ocean" and (chance>=100 or math.fmod(rng_int(), 100)<chance) then
             rn.terrain = "packice"
         end
     end
 end
 
 local function thaw(r, chance)
-    if chance>=100 or math.mod(rng_int(), 100)<chance then
+    if chance>=100 or math.fmod(rng_int(), 100)<chance then
         r.terrain = "ocean"
         for s in r.ships do
             s.coast = nil
diff --git a/scripts/eressea/adamant.lua b/scripts/eressea/adamant.lua
index dae8b7929..003403c13 100644
--- a/scripts/eressea/adamant.lua
+++ b/scripts/eressea/adamant.lua
@@ -3,7 +3,7 @@
 -- use only once to hand out some items to existing factions
 function adamant_gifts()
   for f in factions() do
-    local i = math.mod(test.rng_int(), 2)
+    local i = math.fmod(test.rng_int(), 2)
     if i==0 then
       f:add_item("adamantium", 1)
       f:add_item("adamantiumplate", 1)
diff --git a/scripts/eressea/igjaruk.lua b/scripts/eressea/igjaruk.lua
index 24a095742..155e83283 100644
--- a/scripts/eressea/igjaruk.lua
+++ b/scripts/eressea/igjaruk.lua
@@ -39,7 +39,7 @@ function wyrm()
  local r
  for index, r in pairs(map) do
   if r~=grave then
-   if (math.mod(r.x,2)==math.mod(get_turn(),2)) then
+   if (math.fmod(r.x,2)==math.fmod(get_turn(),2)) then
      r:add_notice("Eine Botschaft von Igjarjuk, Herr der Wyrme: 'Die Zeit des Wartens ist beinahe vorrüber. Euer Fürst kehrt aus dem Grabe zurück.'")
    else
      r:add_notice("Eine Botschaft von Gwaewar, Herr der Greife: 'Das Ende naht. Igjarjuk ist aus seinem Grab auferstanden. Eilt, noch ist die Welt zu retten!'")
diff --git a/scripts/eressea/tunnels.lua b/scripts/eressea/tunnels.lua
index 283cbab5b..2c96be14a 100644
--- a/scripts/eressea/tunnels.lua
+++ b/scripts/eressea/tunnels.lua
@@ -34,7 +34,7 @@ local function get_target(param)
   if ntargets==0 then
     return nil
   end
-  local rn = math.mod(rng_int(), ntargets)
+  local rn = math.fmod(rng_int(), ntargets)
   return targets[rn]
 end