diff --git a/bbb/oderhs.m b/bbb/oderhs.m
index 2cfc53c6..acc9097c 100755
--- a/bbb/oderhs.m
+++ b/bbb/oderhs.m
@@ -614,6 +614,7 @@ subroutine pandf (xc, yc, neq, time, yl, yldot)
       Use(Timing)   # istimingon,ttotfe,ttotjf,ttimpfe,ttimpjf,ttnpg
       Use(Share)    # nxpt,nxomit,geometry,nxc,cutlo,islimon,ix_lim,iy_lims
                     # istabon,isudsym
+      Use(Math_problem_size)   # neqmx,numvar
       Use(Phyvar)   # pi,me,mp,ev,qe,rt8opi
       Use(UEpar)    # methe,methu,methn,methi,methg,concap,lnlam,
                     # convis,icnuiz,icnucx,cnuiz,cnucx,isrecmon,