XF2 json_decode problem

[tr1cky]

This is regarding XF2:

Let's say, I want to read out the content of xf_payment_provider_log -> log_details:

$row = json_decode($row['log_details'], true);
print_r ($row);

Works fine.

But, if there are any special characters in the original log_details entry, nothing is returned.
How would I circumvent this?

Regards

tr1cky