Problem integrating TCPDF

[eluser]Unknown[/eluser]

Following the instructions here: https://github.com/EllisLab/CodeIgniter/...ntegration

I have downloaded latest TCPDF ( tcpdf_6_0_079.zip )

After following the steps for integration I get this error:

Fatal error: Can't use function return value in write context in /xxxx/application/libraries/tcpdf/tcpdf.php on line 22082

Any ideas what I am missing?