MOST FEDERAL white-collar workers were

less than giddy a few weeks ago when President Reagan proposed an annual pay raise for them of 4.8 percent. But the news this week that he would like the same raise for senior government executives must be music to the frozen little ears of these employees, who have not seen an extra penny--not one --in four years. After all this time, they deserve a break today.

True, their current salaries may not be the stuff of which poverty is made. But when you freeze everyone's pay at the top for four years, the crowd bumping against the ceiling gets thicker, incentives get thinner and valuable experience and talents vanish into retirement, which at prevailing pension rates can prove more lucrative than staying on the job.

That's hardly the formula for top-flight management in government, which is why Congress should support the administration's recommendation to end the freeze and to offer the same modest rate of increase proposed for all other federal white-collar workers. It is not a matter of "comparability" with whatever a worker's supposed counterpart in private business may be earning, but with whatever others down through the federal ranks may be getting.

Still better, of course, would be a federal pay structure that took into consideration 1)regional differences in costs of living and pay scales and 2)-- would you believe?--the value of the work performed by each employee. That may be too much to ask, but then, who is footing the bill, and how much is too much to pay?