setfont(pdf_font('jfont', jfont, getfullfontname, getbold, setitalic, setcolor, getface, getstyle, setbold, lowagiefont, setsize, getencoding, istruetype,
setunderline, getcolor, getsize, jfont=, setface, setjfont, oncreate, getsupportedencodings, getunderline, textwidth, getpsfontname, getitalic))
/_init.pdf.lasso (581, 39, 7)

callint(jobject('_private_jni_', ondestroy, asstring), setFont, (Lcom/lassosoft/tags/PDFFont;)I, jobject('_private_jni_', ondestroy, asstring))
/_init.pdf.lasso (58, 4, 3)

chk(jnienv('_private_jnienv_', callobjectmethod, calllongmethod, callnonvirtualbytemethod, callnonvirtualdoublemethod, getcharfield, setobjectfield, setlo
ngfield, callstaticbytemethod, callstaticdoublemethod, getstaticcharfield, setstaticobjectfield, setstaticlongfield, getarraylength, newchararray, getbool
eanarrayelements, getfloatarrayelements, getintarrayregion, getfloatarrayregion, setintarrayregion, fromreflectedmethod, exceptionoccurred, deletelocalref
, getmethodid, callintmethod, callnonvirtualbooleanmethod, callnonvirtualfloatmethod, getbytefield, getdoublefield, setintfield, callstaticbooleanmethod,
callstaticfloatmethod, getstaticbytefield, getstaticdoublefield, setstaticintfield, getstringchars, newbytearray, newdoublearray, getlongarrayelements, ge
tshortarrayregion, getlongarrayregion, setshortarrayregion, monitorexit, thrownew, deleteglobalref, isinstanceof, callshortmethod, callnonvirtualobjectmet
hod, callnonvirtuallongmethod, getbooleanfield, getfloatfield, setshortfield, callstaticobjectmethod, callstaticlongmethod, getstaticbooleanfield, getstat
icfloatfield, setstaticshortfield, getstringlength, newbooleanarray, newfloatarray, getintarrayelements, getchararrayregion, setchararrayregion, monitoren
ter, exceptioncheck, throw, newglobalref, getobjectclass, callcharmethod, callvoidmethod, callnonvirtualintmethod, getobjectfield, getlongfield, setcharfi
eld, getstaticmethodid, callstaticintmethod, getstaticobjectfield, getstaticlongfield, setstaticcharfield, newstring, setobjectarrayelement, newlongarray,
getshortarrayelements, getbytearrayregion, setbytearrayregion, setdoublearrayregion, toreflectedfield, findclass, fatalerror, newobject, callbytemethod,
calldoublemethod, callnonvirtualshortmethod, getfieldid, getintfield, setbytefield, setdoublefield, callstaticshortmethod, getstaticfieldid, getstaticintf
ield, setstaticbytefield, setstaticdoublefield, getobjectarrayelement, newintarray, getchararrayelements, getbooleanarrayregion, setbooleanarrayregion, se
tfloatarrayregion, toreflectedmethod, getversion, exceptionclear, allocobject, callbooleanmethod, callfloatmethod, callnonvirtualcharmethod, callnonvirtua
lvoidmethod, getshortfield, setbooleanfield, setfloatfield, callstaticcharmethod, callstaticvoidmethod, getstaticshortfield, setstaticbooleanfield, setsta
ticfloatfield, newobjectarray, newshortarray, getbytearrayelements, getdoublearrayelements, getdoublearrayregion, setlongarrayregion, fromreflectedfield,
exceptiondescribe, issameobject))
/_init.pdf.lasso (0, 0, 0)

chk(jnienv('_private_jnienv_', callobjectmethod, calllongmethod, callnonvirtualbytemethod, callnonvirtualdoublemethod, getcharfield, setobjectfield, setlo
ngfield, callstaticbytemethod, callstaticdoublemethod, getstaticcharfield, setstaticobjectfield, setstaticlongfield, getarraylength, newchararray, getbool
eanarrayelements, getfloatarrayelements, getintarrayregion, getfloatarrayregion, setintarrayregion, fromreflectedmethod, exceptionoccurred, deletelocalref
, getmethodid, callintmethod, callnonvirtualbooleanmethod, callnonvirtualfloatmethod, getbytefield, getdoublefield, setintfield, callstaticbooleanmethod,
callstaticfloatmethod, getstaticbytefield, getstaticdoublefield, setstaticintfield, getstringchars, newbytearray, newdoublearray, getlongarrayelements, ge
tshortarrayregion, getlongarrayregion, setshortarrayregion, monitorexit, thrownew, deleteglobalref, isinstanceof, callshortmethod, callnonvirtualobjectmet
hod, callnonvirtuallongmethod, getbooleanfield, getfloatfield, setshortfield, callstaticobjectmethod, callstaticlongmethod, getstaticbooleanfield, getstat
icfloatfield, setstaticshortfield, getstringlength, newbooleanarray, newfloatarray, getintarrayelements, getchararrayregion, setchararrayregion, monitoren
ter, exceptioncheck, throw, newglobalref, getobjectclass, callcharmethod, callvoidmethod, callnonvirtualintmethod, getobjectfield, getlongfield, setcharfi
eld, getstaticmethodid, callstaticintmethod, getstaticobjectfield, getstaticlongfield, setstaticcharfield, newstring, setobjectarrayelement, newlongarray,
getshortarrayelements, getbytearrayregion, setbytearrayregion, setdoublearrayregion, toreflectedfield, findclass, fatalerror, newobject, callbytemethod,
calldoublemethod, callnonvirtualshortmethod, getfieldid, getintfield, setbytefield, setdoublefield, callstaticshortmethod, getstaticfieldid, getstaticintf
ield, setstaticbytefield, setstaticdoublefield, getobjectarrayelement, newintarray, getchararrayelements, getbooleanarrayregion, setbooleanarrayregion, se
tfloatarrayregion, toreflectedmethod, getversion, exceptionclear, allocobject, callbooleanmethod, callfloatmethod, callnonvirtualcharmethod, callnonvirtua
lvoidmethod, getshortfield, setbooleanfield, setfloatfield, callstaticcharmethod, callstaticvoidmethod, getstaticshortfield, setstaticbooleanfield, setsta
ticfloatfield, newobjectarray, newshortarray, getbytearrayelements, getdoublearrayelements, getdoublearrayregion, setlongarrayregion, fromreflectedfield,
exceptiondescribe, issameobject))
/_init.pdf.lasso (137, 4, 4)

var( pdfObj ) = PDF_Doc( -file='PdfFontGetColor.pdf',
-format='pdf',
-size= 'a4',
-margins=Array( 18, 18, 18, 18 ),
-color='#00bbff',
-usedate=true,
-nocompress=false,
-header='Testing of the Font Tags',
-pageno=1 );
var( fObj ) = PDF_Font( -face='Helvetica', -size=12, -color='#00ff00', -encoding='Cp1252', -embed=true );
$pdfObj->setFont( $fObj );
$pdfObj->close( );

I think this happens because the doc is totally empty. If I add this right after ->setFont, it works:

$pdfObj->addText( 'Hello, world!', -font=$fObj );