gnus-extract-address-components

gnus-extract-address-components is a variable defined in `gnus.el'.
Its value is

gnus-extract-address-components

Documentation:
*Function for extracting address components from a From header.
Two pre-defined function exist: `gnus-extract-address-components',
which is the default, quite fast, and too simplistic solution, and
`mail-extract-address-components', which works much better, but is
slower.

You can customize this variable.