[ns] error msg: "bailing in Tcl::eval"

[L H]

Hello all,

When I run wireless sensor network simulation using ns2.1b5, my simulator 
works with 100 nodes, 200 nodes, however, when I increased the number of 
nodes to 300 nodes, I got this error message

"bailing in Tcl::eval"

I checked and found that this error message should be generated by the 
program Tcl.cc
below is the related part of the codes in Tcl.cc

void Tcl::eval()
{
        char* p = bp_;
        bp_ = p + strlen(p) + 1;
        /*XXX*/
        if (bp_ >= &buffer_[1024]) {
                fprintf(stderr, "bailing in Tcl::eval\n");
                assert(0);
                exit(1);
        }
        eval(p);
        bp_ = p;
}

You may find the full Tcl.cc program here:
http://www.cs.ucla.edu/classes/winter02/cs216/l1/nssat/build/ns-allinone-2.1b8a/tclcl-1.0b11/Tcl.cc


After I deleted this    

          if (bp_ >= &buffer_[1024]) {
                fprintf(stderr, "bailing in Tcl::eval\n");
                assert(0);
                exit(1);
        }

and do a make again, but the problem is still there when I run the 
simulation.

Could anyone suggest me how to fix this error?  
Thanks in advance!

Jack