diff --git a/DAMASK_env.sh b/DAMASK_env.sh
index 078dd582b..0ae3a2abf 100644
--- a/DAMASK_env.sh
+++ b/DAMASK_env.sh
@@ -39,12 +39,15 @@ fi
 
 # according to http://software.intel.com/en-us/forums/topic/501500
 # this seems to make sense for the stack size
-FREE=$(which free 2>/dev/null)
+FREE=$(type -p free 2>/dev/null)
 if [ "x$FREE" != "x" ]; then
   freeMem=$(free -k | grep -E '(Mem|Speicher):' | awk '{print $4;}')
   # http://superuser.com/questions/220059/what-parameters-has-ulimit             
-  ulimit -d $(expr $freeMem                       / 2)  2>/dev/null # maximum  heap size (kB)
-  ulimit -s $(expr $freeMem / $DAMASK_NUM_THREADS / 2)  2>/dev/null # maximum stack size (kB)
+  ulimit -d unlimited 2>/dev/null \
+  || ulimit -d $(expr $freeMem                       / 2)  2>/dev/null # maximum  heap size (kB)
+  ulimit -s unlimited 2>/dev/null \
+  || echo "cannot unlimit stack..." \
+  && ulimit -s $(expr $freeMem / $DAMASK_NUM_THREADS / 2)  2>/dev/null # maximum stack size (kB)
 fi
 ulimit -v unlimited   2>/dev/null # maximum virtual memory size
 ulimit -m unlimited   2>/dev/null # maximum physical memory size