Memory problems or not?

["natalie nicholls (IAH-C)" <natalie.nicholls@bbsrc.ac.uk>]

I'm receiving this message while trying to run a Lme - any suggestions as to 
what's going wrong (I'm relatively new to using S Plus:

Problem in .C("mixed_loglik",: Unable to obtain requested dynamic memory, while 
calling
 subroutine mixed_loglik 
Use traceback() to see the call stack

Traqceback() gives:
16: eval(action, sys.parent())
15: doErrorAction("Problem in .C(\"mixed_loglik\",: Unable to obtain requested 
dynamic 
memory, while calling subroutine mixed_loglik",
14: .C("mixed_loglik",
13: .C("mixed_loglik",
12: logLik.lmeStructInt(lmeSt, lmePars)
11: logLik(lmeSt, lmePars)
10:  - logLik(lmeSt, lmePars)
9: .C("setup_min",
8: ms( ~  - logLik(lmeSt, lmePars), start = list(lmePars = c(coef(lmeSt))), 
control = 
7: NULL
6: ms( ~  - logLik(lmeSt, lmePars), start = list(lmePars = c(coef(lmeSt))), 
control = 
5: lme.formula(fixed = X8wk.wt ~ Sex + Geno, data = d34, random =  ~ Sire | 
YoB, method
4: eval(fun.call)
3: menuLme(fixed = X8wk.wt ~ Sex + Geno, data = d34, random =  ~ Sire | YoB, 
na.omit.p 
= 
2: eval(expression(model <- menuLme(fixed = X8wk.wt ~ Sex + Geno, data = d34, 
random = 
 ~
1: 
Message: Problem in .C("mixed_loglik",: Unable to obtain requested dynamic 
memory, whil
e calling subroutine mixed_loglik