Help to implement mod

[BoRoU]

Hello, nice to everyone.

I'm trying to adapt this mod to my forum vb4.1.3.

https://vborg.vbsupport.ru/showthrea...118473&page=10

I've managed to make everything more or less the same. The explanation is said to bear all the tables in the same BD, and I rather put it all on the same BD I have given on behalf of the BD "mother" in the amendments to be done.
Apparently everything works fine, except sending PM. Every time I try to send a PM I say this ...

Parse error: syntax error, unexpected '[' in / home / borou / Desktop / www / webs / ERDM / forum / includes / class_dm_pm.php on line 539

The problem is exactly in this line ...

$pmtextid = ($this->existing['pmtextid'] ? $this->existing['pmtextid'] : $this->pmtext['pmtextid']);

$pmtextid = ($this->existing['pmtextid'] ? $this->existing['pmtextid'] : $this->erds.vb2_pmtext['pmtextid']);

Then I skip the error at the point that I have to say that BD is. Above is the code file origial and under the amended.
That could change that code to not give me the error?

THANKS.