I have a alphanumeric list as -

FM2130
FM613
FM3126
FM10
FM76
FM4120

I need it in an order as -

FM10
FM76
FM613
FM2130
FM3126
FM4120

It gets sorted as -

FM2130
FM3126
FM4120
FM10
FM76
FM613

The problem is that blanks need to be in a sort sequence first not last. How
do I fix this for all sorts.