Error - Cannot access display string yet for new node creation in Omnet

I am trying to create a node at run time in my module in Omnet. I am able to create it with this code and its working fine.

cModule* parentmod = getParentModule();
cModule* grantParentMod = parentmod->getParentModule();
cModule* grantParentMod1 = grantParentMod->getParentModule();
// To check if the module is already created
for (cSubModIterator iter(*grantParentMod1); !iter.end(); iter++)
{
    EV << iter()->getFullName()<<endl;
    if (iter()->getFullName() == "host_send4")
        return;
 }
cModuleType *meshnode1 = cModuleType::get("inet.networklayer.manetrouting.PASER.meshnode");
cModule *mod = meshnode1->create("host_send4", grantParentMod1);
cDisplayString& dispstr =  getDisplayString();
dispstr.parse("p=1000,535;r=200,green");
mod->finalizeParameters();
mod->buildInside();
mod->scheduleStart(simTime()+2*beaconInterval);

However this module is not generated at desired place in simulation output (the coordinates and the display). I believe the display string created here is not attached to the module and hence I tried to do it by this :-

cDisplayString& dispstr =  getDisplayString();
dispstr.parse("p=1000,535;r=200,green");
mod->getDisplayString().set(dispstr);

But with this I encounter following error at run time :- Cannot access display string yet: Parameters not yet set up . I know the problem is in mod->getDisplayString().set(dispstr); So is there any other way to assign the parameter or am I doing some minor error. Thanks for this help.