diff -r1.59 PDFRenderer.java
488,489c488,489
< 	    if (kerningAvailable && (i+1) < l) {
< 		pdf.append(addKerning((new Integer((int)ch)),
---
>             if (kerningAvailable && (i+1) < l) {
>                 addKerning(pdf, (new Integer((int)ch)),
567c567,568
<    private StringBuffer addKerning(Integer ch1, Integer ch2,
---
>    private void addKerning(StringBuffer buf,
>                                    Integer ch1, Integer ch2,
571,572d571
<       int pwdt=0;
<       StringBuffer buf=new StringBuffer("");
577,578c576,580
<             pwdt=-wdt.intValue();
<             buf=buf.append(endText + " " + pwdt + " " + startText);
---
>             buf.append(endText)
>                .append(' ')
>                .append(-wdt.intValue())
>                .append(' ')
>                .append(startText);
581d582
<       return buf;