Having an interesting issue with the Spring @Value annotation using SpEL. Setting default value of null works for a String variable. However, for a Set variable it doesn't.

So, this works (varStr is null):

```
@Value("${var.string:#{NULL}}")
private String varStr;

```

while this doesn't (varSet now contains one element with "#{NULL}"):

```
@Value("#{'${var.set:#{NULL}}'.split(',')}")
private Set<String> varSet;

```

The question is how to make this work with a Set variable as well so it would be set to null by default.

Your help will be greatly appreciated.