What is wrong with this code?

[Jeffb]

I downloaded some code and I get this error. It looks ok to me.

Here's the declaration in the .h file.

void SetBorder( bool useBorder,  QBrush& borderBrush = QBrush() );

void SetBorder( bool useBorder,  QBrush& borderBrush = QBrush() );

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Here's the .cpp code:

void JBWidget::SetBorder( bool useBorder, QBrush& borderBrush )
{
      .....
}

void JBWidget::SetBorder( bool useBorder, QBrush& borderBrush )
{
      .....
}

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Here's the error:
error: default argument for parameter of type 'QBrush&' has type 'QBrush'

Why can't it do this?

Cheers
Jeff