pdftoipe does not compile with poppler 0.20

The error function in poppler has changed from version 0.18 
to 0.20 and as a result pdftoipe does not compile with poppler
0.20.

I noticed this problem in a mac with macports after a recent
upgrade. Here is the compilation error:

$ sudo port -vc install ipe-tools -python27
--->  Computing dependencies for ipe-tools.
--->  Building ipe-tools
make: Nothing to be done for `all'.
make: Nothing to be done for `all'.
/usr/bin/clang++ -O2 -arch x86_64 -Wno-write-strings -I/opt/local/include -I/opt/local/include/poppler     -c -o xmloutputdev.o xmloutputdev.cpp
xmloutputdev.cpp:33:5: error: no matching function for call to 'error'
    error(-1, "Couldn't open output file '%s'", fileName);
    ^~~~~
/opt/local/include/poppler/Error.h:54:19: note: candidate function not viable: no known conversion from 'int' to 'ErrorCategory' for 1st argument; 
extern void CDECL error(ErrorCategory category, int pos, const char *msg, ...);
                  ^
1 error generated.
make: *** [xmloutputdev.o] Error 1


The problem can be fixed by changing line 33 of xmloutputdev.cpp from: 

    error(-1, "Couldn't open output file '%s'", fileName);

to the following:

    error(errIO, -1, "Couldn't open output file '%s'", fileName);

Best,
Panos