Box not drawn under strange circumstances

[LaurenzWiskott]

I use dot2tex version 2.9.0 from my Ubuntu distribution. I have tried to generate minimal examples to show what I believe is a bug. When I compile either of the two following files with the command given in the file, one box is not drawn (A in first and B in second example), see attached pdfs.

File test-dot2tex-bug.gv

// REPRODUCE BUG BY RUNNING
// dot -Txdot test-dot2tex-bug.gv | dot2tex | sed 's/\documentclass{article}/\documentclass[margin=5mm]{standalone}/'| sed 's/\enlargethispage{100cm}//' > test-dot2tex-bug.tex ; pdflatex test-dot2tex-bug.tex 
// IT WORKS WITH THOUGH
// dot2tex --preproc test-dot2tex-bug.gv | dot2tex | sed 's/\documentclass{article}/\documentclass[margin=5mm]{standalone}/'| sed 's/\enlargethispage{100cm}//' > test-dot2tex-bug.tex ; pdflatex test-dot2tex-bug.tex

digraph G {

node [shape=box];

A [label="1 Overview (7)"];
B [label="2 Hard partitional clustering (20)"];

A -> B;

};

Result:
test-dot2tex-bug.pdf

File test-dot2tex-bugEvenWithPreproc.gv

// REPRODUCE BUG BY RUNNING
// dot -Txdot test-dot2tex-bug.gv | dot2tex | sed 's/\documentclass{article}/\documentclass[margin=5mm]{standalone}/'| sed 's/\enlargethispage{100cm}//' > test-dot2tex-bug.tex ; pdflatex test-dot2tex-bug.tex 
// OR
// dot2tex --preproc test-dot2tex-bugEvenWithPreproc.gv | dot2tex | sed 's/\documentclass{article}/\documentclass[margin=5mm]{standalone}/'| sed 's/\enlargethispage{100cm}//' > test-dot2tex-bugEvenWithPreproc.tex ; pdflatex test-dot2tex-bugEvenWithPreproc.tex

digraph G {
rankdir=LR

node [shape=box];

A [label="A"];
B [label="B"];
C [label="CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC"];

A -> B
A -> C

}

Result:
test-dot2tex-bugEvenWithPreproc.pdf